{
"query": {
"display": "$$\\cos\\left(1110^{\\circ\\:}\\right)$$",
"symbolab_question": "TRIG_EVALUATE#\\cos(1110^{\\circ })"
},
"solution": {
"level": "PERFORMED",
"subject": "Trigonometry",
"topic": "Evaluate Functions",
"subTopic": "Simplified",
"default": "\\frac{\\sqrt{3}}{2}",
"decimal": "0.86602…",
"meta": {
"showVerify": true
}
},
"steps": {
"type": "interim",
"title": "$$\\cos\\left(1110^{\\circ\\:}\\right)=\\frac{\\sqrt{3}}{2}$$",
"input": "\\cos\\left(1110^{\\circ\\:}\\right)",
"steps": [
{
"type": "interim",
"title": "$$\\cos\\left(1110^{\\circ\\:}\\right)=\\cos\\left(30^{\\circ\\:}\\right)$$",
"input": "\\cos\\left(1110^{\\circ\\:}\\right)",
"result": "=\\cos\\left(30^{\\circ\\:}\\right)",
"steps": [
{
"type": "step",
"primary": "Rewrite $$1110^{\\circ\\:}$$ as $$360^{\\circ\\:}\\cdot\\:3+30^{\\circ\\:}$$",
"result": "=\\cos\\left(360^{\\circ\\:}3+30^{\\circ\\:}\\right)"
},
{
"type": "step",
"primary": "Apply the periodicity of $$\\cos$$: $$\\cos\\left(x+360^{\\circ\\:}\\cdot\\:k\\right)=\\cos\\left(x\\right)$$",
"secondary": [
"$$\\cos\\left(360^{\\circ\\:}\\cdot\\:3+30^{\\circ\\:}\\right)=\\cos\\left(30^{\\circ\\:}\\right)$$"
],
"result": "=\\cos\\left(30^{\\circ\\:}\\right)"
}
],
"meta": {
"interimType": "N/A"
}
},
{
"type": "interim",
"title": "Use the following trivial identity:$${\\quad}\\cos\\left(30^{\\circ\\:}\\right)=\\frac{\\sqrt{3}}{2}$$",
"input": "\\cos\\left(30^{\\circ\\:}\\right)",
"steps": [
{
"type": "step",
"primary": "$$\\cos\\left(x\\right)$$ periodicity table with $$360^{\\circ\\:}n$$ cycle:<br/>$$\\begin{array}{|c|c|c|c|}\\hline x&\\cos(x)&x&\\cos(x)\\\\\\hline 0&1&180^{\\circ }&-1\\\\\\hline 30^{\\circ }&\\frac{\\sqrt{3}}{2}&210^{\\circ }&-\\frac{\\sqrt{3}}{2}\\\\\\hline 45^{\\circ }&\\frac{\\sqrt{2}}{2}&225^{\\circ }&-\\frac{\\sqrt{2}}{2}\\\\\\hline 60^{\\circ }&\\frac{1}{2}&240^{\\circ }&-\\frac{1}{2}\\\\\\hline 90^{\\circ }&0&270^{\\circ }&0\\\\\\hline 120^{\\circ }&-\\frac{1}{2}&300^{\\circ }&\\frac{1}{2}\\\\\\hline 135^{\\circ }&-\\frac{\\sqrt{2}}{2}&315^{\\circ }&\\frac{\\sqrt{2}}{2}\\\\\\hline 150^{\\circ }&-\\frac{\\sqrt{3}}{2}&330^{\\circ }&\\frac{\\sqrt{3}}{2}\\\\\\hline \\end{array}$$"
},
{
"type": "step",
"result": "=\\frac{\\sqrt{3}}{2}"
}
],
"meta": {
"interimType": "Trig Trivial Angle Value Title 0Eq"
}
},
{
"type": "step",
"result": "=\\frac{\\sqrt{3}}{2}"
}
],
"meta": {
"solvingClass": "Trig Evaluate",
"practiceLink": "/practice/trigonometry-practice#area=main&subtopic=Evaluate%20Functions",
"practiceTopic": "Evaluate Functions"
}
},
"meta": {
"showVerify": true
}
}
Solution
Solution
+1
Decimal
Solution steps
Rewrite as
Apply the periodicity of :
Use the following trivial identity:
periodicity table with cycle:
Popular Examples
Frequently Asked Questions (FAQ)
What is the value of cos(1110) ?
The value of cos(1110) is (sqrt(3))/2