{
"query": {
"display": "$$\\tan\\left(\\frac{7π}{4}\\right)$$",
"symbolab_question": "TRIG_EVALUATE#\\tan(\\frac{7π}{4})"
},
"solution": {
"level": "PERFORMED",
"subject": "Trigonometry",
"topic": "Evaluate Functions",
"subTopic": "Simplified",
"default": "-1",
"meta": {
"showVerify": true
}
},
"steps": {
"type": "interim",
"title": "$$\\tan\\left(\\frac{7π}{4}\\right)=-1$$",
"input": "\\tan\\left(\\frac{7π}{4}\\right)",
"steps": [
{
"type": "interim",
"title": "$$\\tan\\left(\\frac{7π}{4}\\right)=\\tan\\left(\\frac{3π}{4}\\right)$$",
"input": "\\tan\\left(\\frac{7π}{4}\\right)",
"result": "=\\tan\\left(\\frac{3π}{4}\\right)",
"steps": [
{
"type": "step",
"primary": "Rewrite $$\\frac{7π}{4}$$ as $$π+\\frac{3π}{4}$$",
"result": "=\\tan\\left(π+\\frac{3π}{4}\\right)"
},
{
"type": "step",
"primary": "Apply the periodicity of $$\\tan$$: $$\\tan\\left(x+π\\right)=\\tan\\left(x\\right)$$",
"secondary": [
"$$\\tan\\left(π+\\frac{3π}{4}\\right)=\\tan\\left(\\frac{3π}{4}\\right)$$"
],
"result": "=\\tan\\left(\\frac{3π}{4}\\right)"
}
],
"meta": {
"interimType": "N/A"
}
},
{
"type": "interim",
"title": "Rewrite using trig identities:$${\\quad}\\frac{\\sin\\left(\\frac{3π}{4}\\right)}{\\cos\\left(\\frac{3π}{4}\\right)}$$",
"input": "\\tan\\left(\\frac{3π}{4}\\right)",
"result": "=\\frac{\\sin\\left(\\frac{3π}{4}\\right)}{\\cos\\left(\\frac{3π}{4}\\right)}",
"steps": [
{
"type": "step",
"primary": "Use the basic trigonometric identity: $$\\tan\\left(x\\right)=\\frac{\\sin\\left(x\\right)}{\\cos\\left(x\\right)}$$",
"result": "=\\frac{\\sin\\left(\\frac{3π}{4}\\right)}{\\cos\\left(\\frac{3π}{4}\\right)}"
}
],
"meta": {
"interimType": "Trig Rewrite Using Trig identities Title 0Eq"
}
},
{
"type": "interim",
"title": "Use the following trivial identity:$${\\quad}\\sin\\left(\\frac{3π}{4}\\right)=\\frac{\\sqrt{2}}{2}$$",
"input": "\\sin\\left(\\frac{3π}{4}\\right)",
"steps": [
{
"type": "step",
"primary": "$$\\sin\\left(x\\right)$$ periodicity table with $$2πn$$ cycle:<br/>$$\\begin{array}{|c|c|c|c|}\\hline x&\\sin(x)&x&\\sin(x)\\\\\\hline 0&0&π&0\\\\\\hline \\frac{π}{6}&\\frac{1}{2}&\\frac{7π}{6}&-\\frac{1}{2}\\\\\\hline \\frac{π}{4}&\\frac{\\sqrt{2}}{2}&\\frac{5π}{4}&-\\frac{\\sqrt{2}}{2}\\\\\\hline \\frac{π}{3}&\\frac{\\sqrt{3}}{2}&\\frac{4π}{3}&-\\frac{\\sqrt{3}}{2}\\\\\\hline \\frac{π}{2}&1&\\frac{3π}{2}&-1\\\\\\hline \\frac{2π}{3}&\\frac{\\sqrt{3}}{2}&\\frac{5π}{3}&-\\frac{\\sqrt{3}}{2}\\\\\\hline \\frac{3π}{4}&\\frac{\\sqrt{2}}{2}&\\frac{7π}{4}&-\\frac{\\sqrt{2}}{2}\\\\\\hline \\frac{5π}{6}&\\frac{1}{2}&\\frac{11π}{6}&-\\frac{1}{2}\\\\\\hline \\end{array}$$"
},
{
"type": "step",
"result": "=\\frac{\\sqrt{2}}{2}"
}
],
"meta": {
"interimType": "Trig Trivial Angle Value Title 0Eq"
}
},
{
"type": "interim",
"title": "Use the following trivial identity:$${\\quad}\\cos\\left(\\frac{3π}{4}\\right)=-\\frac{\\sqrt{2}}{2}$$",
"input": "\\cos\\left(\\frac{3π}{4}\\right)",
"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": "=-\\frac{\\sqrt{2}}{2}"
}
],
"meta": {
"interimType": "Trig Trivial Angle Value Title 0Eq"
}
},
{
"type": "step",
"result": "=\\frac{\\frac{\\sqrt{2}}{2}}{-\\frac{\\sqrt{2}}{2}}"
},
{
"type": "interim",
"title": "Simplify $$\\frac{\\frac{\\sqrt{2}}{2}}{-\\frac{\\sqrt{2}}{2}}:{\\quad}-1$$",
"input": "\\frac{\\frac{\\sqrt{2}}{2}}{-\\frac{\\sqrt{2}}{2}}",
"result": "=-1",
"steps": [
{
"type": "step",
"primary": "Apply the fraction rule: $$\\frac{a}{-b}=-\\frac{a}{b}$$",
"result": "=-\\frac{\\frac{\\sqrt{2}}{2}}{\\frac{\\sqrt{2}}{2}}"
},
{
"type": "step",
"primary": "Divide fractions: $$\\frac{\\frac{a}{b}}{\\frac{c}{d}}=\\frac{a\\cdot\\:d}{b\\cdot\\:c}$$",
"result": "=-\\frac{\\sqrt{2}\\cdot\\:2}{2\\sqrt{2}}"
},
{
"type": "step",
"primary": "Cancel the common factor: $$\\sqrt{2}$$",
"result": "=-\\frac{2}{2}"
},
{
"type": "step",
"primary": "Cancel the common factor: $$2$$",
"result": "=-1"
}
],
"meta": {
"solvingClass": "Solver",
"interimType": "Generic Simplify Specific 1Eq",
"gptData": "pG0PljGlka7rWtIVHz2xymbOTBTIQkBEGSNjyYYsjjDErT97kX84sZPuiUzCW6s7tiTmKkmeEqHWILbBb88ajbJ3wo1uFgyKliORhBgbJo0ussnnnisJndCAm4z+zno8qSLiRo0DO9IhVuX5Gm3ZK3CQoYlYQ8U+Tfyx0kyzI8hBup7XxSVaYGLLOwF6kQecmNwEgvmmajzdQwVlFLMmxS3xXPiuLkj+jJktEBj2/1IAQNpETCgQ7A7uB2HlXgboNExR2KxRxAUdkyDIsIWVgNpK7SU09JD4Nr69pNDewic="
}
}
],
"meta": {
"solvingClass": "Trig Evaluate",
"practiceLink": "/practice/trigonometry-practice#area=main&subtopic=Evaluate%20Functions",
"practiceTopic": "Evaluate Functions"
}
},
"meta": {
"showVerify": true
}
}
Solution
Solution
Solution steps
Rewrite as
Apply the periodicity of :
Rewrite using trig identities:
Use the basic trigonometric identity:
Use the following trivial identity:
periodicity table with cycle:
Use the following trivial identity:
periodicity table with cycle:
Simplify
Apply the fraction rule:
Divide fractions:
Cancel the common factor:
Cancel the common factor:
Popular Examples
Frequently Asked Questions (FAQ)
What is the value of tan((7pi)/4) ?
The value of tan((7pi)/4) is -1