{
"query": {
"display": "critical points $$x^{4}-x^{2}$$",
"symbolab_question": "FUNCTION#critical x^{4}-x^{2}"
},
"solution": {
"level": "PERFORMED",
"subject": "Functions & Graphing",
"topic": "Functions",
"subTopic": "critical",
"default": "x=-\\frac{1}{\\sqrt{2}},x=0,x=\\frac{1}{\\sqrt{2}}"
},
"steps": {
"type": "interim",
"title": "Critical Points of $$x^{4}-x^{2}:{\\quad}x=-\\frac{1}{\\sqrt{2}},\\:x=0,\\:x=\\frac{1}{\\sqrt{2}}$$",
"input": "x^{4}-x^{2}",
"steps": [
{
"type": "definition",
"title": "Critical point definition",
"text": "Critical points are points where the function is defined and its derivative is zero or undefined"
},
{
"type": "interim",
"title": "Find where $$f^{\\prime}\\left(x\\right)$$ is equal to zero or undefined",
"input": "x^{4}-x^{2}",
"result": "x=-\\frac{1}{\\sqrt{2}},\\:x=0,\\:x=\\frac{1}{\\sqrt{2}}",
"steps": [
{
"type": "interim",
"title": "$$f^{\\prime}\\left(x\\right)=4x^{3}-2x$$",
"input": "\\frac{d}{dx}\\left(x^{4}-x^{2}\\right)",
"steps": [
{
"type": "step",
"primary": "Apply the Sum/Difference Rule: $$\\left(f{\\pm}g\\right)'=f'{\\pm}g'$$",
"result": "=\\frac{d}{dx}\\left(x^{4}\\right)-\\frac{d}{dx}\\left(x^{2}\\right)"
},
{
"type": "interim",
"title": "$$\\frac{d}{dx}\\left(x^{4}\\right)=4x^{3}$$",
"input": "\\frac{d}{dx}\\left(x^{4}\\right)",
"steps": [
{
"type": "step",
"primary": "Apply the Power Rule: $$\\frac{d}{dx}\\left(x^a\\right)=a{\\cdot}x^{a-1}$$",
"result": "=4x^{4-1}",
"meta": {
"practiceLink": "/practice/derivatives-practice#area=main&subtopic=Power%20Rule",
"practiceTopic": "Power Rule"
}
},
{
"type": "step",
"primary": "Simplify",
"result": "=4x^{3}",
"meta": {
"solvingClass": "Solver"
}
}
],
"meta": {
"solvingClass": "Derivatives",
"interimType": "Derivatives",
"gptData": "pG0PljGlka7rWtIVHz2xymbOTBTIQkBEGSNjyYYsjjDErT97kX84sZPuiUzCW6s79Kg+idP5vLVrjUll6eMdYodvM0LC1fPom5KofzCj+6qk3hxk9aCfAWodBRxXgUexGgZz1CFzF7HTa4VF2uoRHv8//6/nV5O4fb8Xgwi7maqO95Is7YBdcRqXmTH8euc2JrcUvyUpj++aXrGYPlvDVw=="
}
},
{
"type": "interim",
"title": "$$\\frac{d}{dx}\\left(x^{2}\\right)=2x$$",
"input": "\\frac{d}{dx}\\left(x^{2}\\right)",
"steps": [
{
"type": "step",
"primary": "Apply the Power Rule: $$\\frac{d}{dx}\\left(x^a\\right)=a{\\cdot}x^{a-1}$$",
"result": "=2x^{2-1}",
"meta": {
"practiceLink": "/practice/derivatives-practice#area=main&subtopic=Power%20Rule",
"practiceTopic": "Power Rule"
}
},
{
"type": "step",
"primary": "Simplify",
"result": "=2x",
"meta": {
"solvingClass": "Solver"
}
}
],
"meta": {
"solvingClass": "Derivatives",
"interimType": "Derivatives",
"gptData": "pG0PljGlka7rWtIVHz2xymbOTBTIQkBEGSNjyYYsjjDErT97kX84sZPuiUzCW6s79Kg+idP5vLVrjUll6eMdYkmb3s5xAUYje7fZWSRkdb2k3hxk9aCfAWodBRxXgUexcQsmN/cITrVSOMImEqe3fkeCBKuYKgaNJ253gLI69U7cjrVUqImvoUuRtb+2ccCzWsr9JoDNJaP7hueshcYJ6w=="
}
},
{
"type": "step",
"result": "=4x^{3}-2x"
}
],
"meta": {
"solvingClass": "Derivatives",
"interimType": "Derivatives"
}
},
{
"type": "interim",
"title": "Solve $$4x^{3}-2x=0:{\\quad}x=0,\\:x=-\\frac{1}{\\sqrt{2}},\\:x=\\frac{1}{\\sqrt{2}}$$",
"input": "4x^{3}-2x=0",
"steps": [
{
"type": "interim",
"title": "Factor $$4x^{3}-2x:{\\quad}2x\\left(\\sqrt{2}x+1\\right)\\left(\\sqrt{2}x-1\\right)$$",
"input": "4x^{3}-2x",
"steps": [
{
"type": "interim",
"title": "Factor out common term $$2x:{\\quad}2x\\left(2x^{2}-1\\right)$$",
"input": "4x^{3}-2x",
"steps": [
{
"type": "step",
"primary": "Apply exponent rule: $$a^{b+c}=a^{b}a^{c}$$",
"secondary": [
"$$x^{3}=x^{2}x$$"
],
"result": "=4x^{2}x-2x",
"meta": {
"practiceLink": "/practice/exponent-practice",
"practiceTopic": "Expand FOIL"
}
},
{
"type": "step",
"primary": "Rewrite $$4$$ as $$2\\cdot\\:2$$",
"result": "=2\\cdot\\:2x^{2}x-2x"
},
{
"type": "step",
"primary": "Factor out common term $$2x$$",
"result": "=2x\\left(2x^{2}-1\\right)"
}
],
"meta": {
"interimType": "Factor Take Out Common Term 1Eq",
"practiceLink": "/practice/factoring-practice",
"practiceTopic": "Factoring"
}
},
{
"type": "step",
"result": "=2x\\left(2x^{2}-1\\right)"
},
{
"type": "interim",
"title": "Factor $$2x^{2}-1:{\\quad}\\left(\\sqrt{2}x+1\\right)\\left(\\sqrt{2}x-1\\right)$$",
"input": "2x^{2}-1",
"steps": [
{
"type": "interim",
"title": "Rewrite $$2x^{2}-1$$ as $$\\left(\\sqrt{2}x\\right)^{2}-1^{2}$$",
"input": "2x^{2}-1",
"result": "=\\left(\\sqrt{2}x\\right)^{2}-1^{2}",
"steps": [
{
"type": "step",
"primary": "Apply radical rule: $$a=\\left(\\sqrt{a}\\right)^{2}$$",
"secondary": [
"$$2=\\left(\\sqrt{2}\\right)^{2}$$"
],
"result": "=\\left(\\sqrt{2}\\right)^{2}x^{2}-1",
"meta": {
"practiceLink": "/practice/radicals-practice",
"practiceTopic": "Radical Rules"
}
},
{
"type": "step",
"primary": "Rewrite $$1$$ as $$1^{2}$$",
"result": "=\\left(\\sqrt{2}\\right)^{2}x^{2}-1^{2}"
},
{
"type": "step",
"primary": "Apply exponent rule: $$a^{m}b^{m}=\\left(ab\\right)^{m}$$",
"secondary": [
"$$\\left(\\sqrt{2}\\right)^{2}x^{2}=\\left(\\sqrt{2}x\\right)^{2}$$"
],
"result": "=\\left(\\sqrt{2}x\\right)^{2}-1^{2}",
"meta": {
"practiceLink": "/practice/exponent-practice",
"practiceTopic": "Expand FOIL"
}
}
],
"meta": {
"interimType": "Generic Rewrite As Specific 2Eq"
}
},
{
"type": "step",
"primary": "Apply Difference of Two Squares Formula: $$x^{2}-y^{2}=\\left(x+y\\right)\\left(x-y\\right)$$",
"secondary": [
"$$\\left(\\sqrt{2}x\\right)^{2}-1^{2}=\\left(\\sqrt{2}x+1\\right)\\left(\\sqrt{2}x-1\\right)$$"
],
"result": "=\\left(\\sqrt{2}x+1\\right)\\left(\\sqrt{2}x-1\\right)",
"meta": {
"practiceLink": "/practice/factoring-practice#area=main&subtopic=Difference%20of%20Two%20Squares",
"practiceTopic": "Factor Difference of Squares"
}
}
],
"meta": {
"interimType": "Algebraic Manipulation Factor Title 1Eq"
}
},
{
"type": "step",
"result": "=2x\\left(\\sqrt{2}x+1\\right)\\left(\\sqrt{2}x-1\\right)"
}
],
"meta": {
"solvingClass": "Solver",
"interimType": "Generic Factor Specific 1Eq"
}
},
{
"type": "step",
"result": "2x\\left(\\sqrt{2}x+1\\right)\\left(\\sqrt{2}x-1\\right)=0"
},
{
"type": "step",
"primary": "Using the Zero Factor Principle:$$\\quad$$ If $$ab=0\\:$$then $$a=0\\:$$or $$b=0$$",
"result": "x=0\\lor\\:\\sqrt{2}x+1=0\\lor\\:\\sqrt{2}x-1=0"
},
{
"type": "interim",
"title": "Solve $$\\sqrt{2}x+1=0:{\\quad}x=-\\frac{1}{\\sqrt{2}}$$",
"input": "\\sqrt{2}x+1=0",
"steps": [
{
"type": "interim",
"title": "Move $$1\\:$$to the right side",
"input": "\\sqrt{2}x+1=0",
"result": "\\sqrt{2}x=-1",
"steps": [
{
"type": "step",
"primary": "Subtract $$1$$ from both sides",
"result": "\\sqrt{2}x+1-1=0-1"
},
{
"type": "step",
"primary": "Simplify",
"result": "\\sqrt{2}x=-1"
}
],
"meta": {
"interimType": "Move to the Right Title 1Eq",
"gptData": "pG0PljGlka7rWtIVHz2xymbOTBTIQkBEGSNjyYYsjjDErT97kX84sZPuiUzCW6s7ECl81GL+sHp+UX1O7owT7bzUFFwS1BPEbS8QldIE/Mpe89ZbiWHFcrwEKQ3Vv1MwgOhFcKXKNhVNjhBHfbnqHxmpvlSOY0AeL0DWrfPlsC6aQOqeLHNy39RIkvHGvclkvFZh+W/iDMDAo4iCI7tFUdwpqaFhGel8eqIiHymEdPNIrutd8eSMgUo+HpRyFwAMy5apAt0FSBwLXftEK0T570tZvy26E9Pk5PNH0yc5TnClNmFO085yUiXdcvIcOuiVVq2M/4aRmPvBMEJFHQhoqsq/8wFSa719RbXg5iOE8hOT/TeRnzjoRVS+qb7rurGKlUxshzZpuGGhK/tWxoxdieUYLJhbzD0L6/vxSHnVIZlgJQOyi0SJ2WijzIA5J6rcOtTUrVkfAODDrUsRVSjTB2aVzveu1K3mCUYj//HI620Vk8t2Twjh+zjp9dlYTco/GgwSbIcd5JjP/d1KuCbW94zDSf2vh/i+3s4cO/oKwZy1rKw+72V41LgxeCOecKXOfIvtRFItCUfO72DblJDvr6ag359nJICSNxR1sdkiJYDwt9LEn7QCBUukJKctfSJKD/3bN2pUHBE+Gg5t9u/d5umzhmTPJ7NSdCx2PBXLC8JGzkFQgw9c9EtLVLoXo8fc"
}
},
{
"type": "interim",
"title": "Divide both sides by $$\\sqrt{2}$$",
"input": "\\sqrt{2}x=-1",
"result": "x=-\\frac{1}{\\sqrt{2}}",
"steps": [
{
"type": "step",
"primary": "Divide both sides by $$\\sqrt{2}$$",
"result": "\\frac{\\sqrt{2}x}{\\sqrt{2}}=\\frac{-1}{\\sqrt{2}}"
},
{
"type": "step",
"primary": "Simplify",
"result": "x=-\\frac{1}{\\sqrt{2}}"
}
],
"meta": {
"interimType": "Divide Both Sides Specific 1Eq",
"gptData": "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"
}
}
],
"meta": {
"solvingClass": "Equations",
"interimType": "Generic Solve Title 1Eq"
}
},
{
"type": "interim",
"title": "Solve $$\\sqrt{2}x-1=0:{\\quad}x=\\frac{1}{\\sqrt{2}}$$",
"input": "\\sqrt{2}x-1=0",
"steps": [
{
"type": "interim",
"title": "Move $$1\\:$$to the right side",
"input": "\\sqrt{2}x-1=0",
"result": "\\sqrt{2}x=1",
"steps": [
{
"type": "step",
"primary": "Add $$1$$ to both sides",
"result": "\\sqrt{2}x-1+1=0+1"
},
{
"type": "step",
"primary": "Simplify",
"result": "\\sqrt{2}x=1"
}
],
"meta": {
"interimType": "Move to the Right Title 1Eq",
"gptData": "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"
}
},
{
"type": "interim",
"title": "Divide both sides by $$\\sqrt{2}$$",
"input": "\\sqrt{2}x=1",
"result": "x=\\frac{1}{\\sqrt{2}}",
"steps": [
{
"type": "step",
"primary": "Divide both sides by $$\\sqrt{2}$$",
"result": "\\frac{\\sqrt{2}x}{\\sqrt{2}}=\\frac{1}{\\sqrt{2}}"
},
{
"type": "step",
"primary": "Simplify",
"result": "x=\\frac{1}{\\sqrt{2}}"
}
],
"meta": {
"interimType": "Divide Both Sides Specific 1Eq",
"gptData": "pG0PljGlka7rWtIVHz2xymbOTBTIQkBEGSNjyYYsjjDErT97kX84sZPuiUzCW6s7ECl81GL+sHp+UX1O7owT7dolLVAPjxCEmufsOneY733Vh90DS7J9J40zZjnm5cN3YIAUidEgplp1JxNyFh4VTR1FxOGHht3VozfO/+GIj2NCfAasBcexWwU2opdbC2IJzwYux9vKbgKMtgQzqXufEYktuuzL09SS3U+RsgxHGFXM/LAqhVuCkTIuc6bWnflIrKAIgmS8W9timVbRiFNYjdgjzvECaIwB5OD9iEObqWJhWYyf+MlLmeC/fptW1Q8xLJB1a9VlJJKEW6KSzQaAOtgY2D+8/PNLtiyUKeYc3kVuvSOcSo4mfYj5J5AakBpjOlBk6i4Fd/0iElf4Lmxk1tkg6O8T23k7bQDKJqmX7xUp1Udffl5xreTptTkdObuMKgIWuQIZV/6HktdBBA0UZJKfjodpUsPd3xljTmrgPzKDZp63hBGhjskvuDfrfb9Z+M47wUwofebcc2b4hlDDCXgdyTSIALeKJHOd0bpb+aksXf9zkGMZrK+UegK8hFqWzbVvsbe2FwB551F3zoabdhcpTddhXB6PpdnfagbEv9x+c/SZGKJlPT9WBkxURag3TeQKHeh69S6dnv9vSoUoFGA0nrsQ4PyW80APeJ9XESgsL1oc9O7HjBFxiMhriWQZvzIPeEtDfcHv/z8uls8Teg=="
}
}
],
"meta": {
"solvingClass": "Equations",
"interimType": "Generic Solve Title 1Eq"
}
},
{
"type": "step",
"primary": "The solutions are",
"result": "x=0,\\:x=-\\frac{1}{\\sqrt{2}},\\:x=\\frac{1}{\\sqrt{2}}"
}
],
"meta": {
"solvingClass": "Equations",
"interimType": "Generic Solve Title 1Eq"
}
},
{
"type": "step",
"result": "x=-\\frac{1}{\\sqrt{2}},\\:x=0,\\:x=\\frac{1}{\\sqrt{2}}"
}
],
"meta": {
"interimType": "Explore Function Slope Zero 1Eq",
"gptData": "pG0PljGlka7rWtIVHz2xymbOTBTIQkBEGSNjyYYsjjDErT97kX84sZPuiUzCW6s7owSbZQBVuOtvRJx3LSI/x4xq2YDRufFWghOsVoHbQs5F+N/82d9gQExbRFw+dZ46O4jPrNVvYsR23FCfYY1xU2RgZdW697FcK7XZ6FFM3ZMskHVr1WUkkoRbopLNBoA6/0zgGGGhNcYTnIAFOctM516rCvntU4ho/UbC5FNDUWB0BOtCKjjO52aLG340IQm6jVF5LdUKmTRWYV+yps/gazxVTC2YiFM25udqOdyHyfkZq8lQPQ/cEZBDLIblagFz"
}
},
{
"type": "step",
"primary": "Identify critical points not in $$f\\left(x\\right)$$ domain"
},
{
"type": "interim",
"title": "Domain of $$x^{4}-x^{2}\\::{\\quad}-\\infty\\:<x<\\infty\\:$$",
"steps": [
{
"type": "definition",
"title": "Domain definition",
"text": "The domain of a function is the set of input or argument values for which the function is real and defined"
},
{
"type": "step",
"primary": "The function has no undefined points nor domain constraints. Therefore, the domain is",
"result": "-\\infty\\:<x<\\infty\\:"
}
],
"meta": {
"solvingClass": "Function Domain",
"interimType": "Function Domain Top 1Eq"
}
},
{
"type": "step",
"primary": "All critical points are in domain",
"result": "x=-\\frac{1}{\\sqrt{2}},\\:x=0,\\:x=\\frac{1}{\\sqrt{2}}"
}
],
"meta": {
"solvingClass": "Function Critical"
}
},
"plot_output": {
"meta": {
"plotInfo": {
"variable": "x",
"plotRequest": "x^{4}-x^{2}"
},
"showViewLarger": true
}
}
}
Solution
critical points
Solution
Solution steps
Find where is equal to zero or undefined
Identify critical points not in domain
Domain of
All critical points are in domain
Graph
Popular Examples
domain of f(x)= 7/(x-4)domain slope of y=11x-5slope critical (x^2-9)^6critical points critical sqrt(4-x^2)critical points range of f(x)=(x+1)/(x-1)range
Frequently Asked Questions (FAQ)
What is the critical x^4-x^2 ?
The critical x^4-x^2 is x=-1/(sqrt(2)),x=0,x= 1/(sqrt(2))