{
"query": {
"display": "$$2\\cos\\left(θ\\right)+\\sqrt{2}=0,\\:0\\le\\:θ\\le\\:2π$$",
"symbolab_question": "EQUATION#2\\cos(θ)+\\sqrt{2}=0,0\\le θ\\le 2π"
},
"solution": {
"level": "PERFORMED",
"subject": "Trigonometry",
"topic": "Trig Equations",
"subTopic": "Trig Equations",
"default": "θ=\\frac{3π}{4},θ=\\frac{5π}{4}",
"degrees": "θ=135^{\\circ },θ=225^{\\circ }",
"meta": {
"showVerify": true
}
},
"steps": {
"type": "interim",
"title": "$$2\\cos\\left(θ\\right)+\\sqrt{2}=0,\\:0\\le\\:θ\\le\\:2π{\\quad:\\quad}θ=\\frac{3π}{4},\\:θ=\\frac{5π}{4}$$",
"input": "2\\cos\\left(θ\\right)+\\sqrt{2}=0,\\:0\\le\\:θ\\le\\:2π",
"steps": [
{
"type": "interim",
"title": "Move $$\\sqrt{2}\\:$$to the right side",
"input": "2\\cos\\left(θ\\right)+\\sqrt{2}=0",
"result": "2\\cos\\left(θ\\right)=-\\sqrt{2}",
"steps": [
{
"type": "step",
"primary": "Subtract $$\\sqrt{2}$$ from both sides",
"result": "2\\cos\\left(θ\\right)+\\sqrt{2}-\\sqrt{2}=0-\\sqrt{2}"
},
{
"type": "step",
"primary": "Simplify",
"result": "2\\cos\\left(θ\\right)=-\\sqrt{2}"
}
],
"meta": {
"interimType": "Move to the Right Title 1Eq",
"gptData": "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"
}
},
{
"type": "interim",
"title": "Divide both sides by $$2$$",
"input": "2\\cos\\left(θ\\right)=-\\sqrt{2}",
"result": "\\cos\\left(θ\\right)=-\\frac{\\sqrt{2}}{2}",
"steps": [
{
"type": "step",
"primary": "Divide both sides by $$2$$",
"result": "\\frac{2\\cos\\left(θ\\right)}{2}=\\frac{-\\sqrt{2}}{2}"
},
{
"type": "step",
"primary": "Simplify",
"result": "\\cos\\left(θ\\right)=-\\frac{\\sqrt{2}}{2}"
}
],
"meta": {
"interimType": "Divide Both Sides Specific 1Eq",
"gptData": "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"
}
},
{
"type": "interim",
"title": "General solutions for $$\\cos\\left(θ\\right)=-\\frac{\\sqrt{2}}{2}$$",
"result": "θ=\\frac{3π}{4}+2πn,\\:θ=\\frac{5π}{4}+2πn",
"steps": [
{
"type": "step",
"primary": "$$\\cos\\left(x\\right)$$ periodicity table with $$2πn$$ cycle:<br/>$$\\begin{array}{|c|c|c|c|}\\hline x&\\cos(x)&x&\\cos(x)\\\\\\hline 0&1&π&-1\\\\\\hline \\frac{π}{6}&\\frac{\\sqrt{3}}{2}&\\frac{7π}{6}&-\\frac{\\sqrt{3}}{2}\\\\\\hline \\frac{π}{4}&\\frac{\\sqrt{2}}{2}&\\frac{5π}{4}&-\\frac{\\sqrt{2}}{2}\\\\\\hline \\frac{π}{3}&\\frac{1}{2}&\\frac{4π}{3}&-\\frac{1}{2}\\\\\\hline \\frac{π}{2}&0&\\frac{3π}{2}&0\\\\\\hline \\frac{2π}{3}&-\\frac{1}{2}&\\frac{5π}{3}&\\frac{1}{2}\\\\\\hline \\frac{3π}{4}&-\\frac{\\sqrt{2}}{2}&\\frac{7π}{4}&\\frac{\\sqrt{2}}{2}\\\\\\hline \\frac{5π}{6}&-\\frac{\\sqrt{3}}{2}&\\frac{11π}{6}&\\frac{\\sqrt{3}}{2}\\\\\\hline \\end{array}$$"
},
{
"type": "step",
"result": "θ=\\frac{3π}{4}+2πn,\\:θ=\\frac{5π}{4}+2πn"
}
],
"meta": {
"interimType": "Trig General Solutions cos 1Eq"
}
},
{
"type": "step",
"primary": "Solutions for the range $$0\\le\\:θ\\le\\:2π$$",
"result": "θ=\\frac{3π}{4},\\:θ=\\frac{5π}{4}"
}
],
"meta": {
"solvingClass": "Trig Equations",
"practiceLink": "/practice/trigonometry-practice#area=main&subtopic=Trig%20Equations",
"practiceTopic": "Trig Equations"
}
},
"plot_output": {
"meta": {
"plotInfo": {
"variable": "θ",
"plotRequest": "2\\cos(θ)+\\sqrt{2},0\\le θ\\le 2π"
},
"showViewLarger": true
}
},
"meta": {
"showVerify": true
}
}
Solution
Solution
+1
Degrees
Solution steps
Move to the right side
Subtract from both sides
Simplify
Divide both sides by
Divide both sides by
Simplify
General solutions for
periodicity table with cycle:
Solutions for the range
Graph
Popular Examples
sqrt(3)tan(θ/2)-1=0tan(x/2)=sqrt(3),0<= x<2pisin(x)= 4/(cos(x))tan^3(x)-2tan(x)=tan(x)sin^2(x)+2cos^2(x)=0
Frequently Asked Questions (FAQ)
What is the general solution for 2cos(θ)+sqrt(2)=0,0<= θ<= 2pi ?
The general solution for 2cos(θ)+sqrt(2)=0,0<= θ<= 2pi is θ=(3pi)/4 ,θ=(5pi)/4