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anonymous
 one year ago
PRECALCULUS: Find the exact value of cos1 the quantity square root of three divided by two.
anonymous
 one year ago
PRECALCULUS: Find the exact value of cos1 the quantity square root of three divided by two.

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anonymous
 one year ago
Best ResponseYou've already chosen the best response.0\[\cos^{1} \left( \frac{ \sqrt{3} }{ 2} \right)\]

anonymous
 one year ago
Best ResponseYou've already chosen the best response.0we know that the range arccos(x) is 0 ≤ x ≤ π/2 ==> 0° ≤ x ≤ 180°. So we need to find the solution to cos(x) = √3/2 this in the range of [0°, 180°]. If we construct a 306090 triangle, we see that the 30° angle corresponds to this and so the angle required is x = 180°  30° = 150°. Thus, arccos(√3/2) = 150° = 5π/6. Answer provided by Yahoo Answers :)

anonymous
 one year ago
Best ResponseYou've already chosen the best response.0The answer amber provided was for \[\sf \large\frac{\sqrt{3}}{2}\] by the way

anonymous
 one year ago
Best ResponseYou've already chosen the best response.0I think your answer is wrong, but the way you explain it is right.

anonymous
 one year ago
Best ResponseYou've already chosen the best response.0I know @LegendarySadist :)

anonymous
 one year ago
Best ResponseYou've already chosen the best response.0The easiest way to go about this sort of problem is simply to utilize the unit circle.

anonymous
 one year ago
Best ResponseYou've already chosen the best response.0For cos, the range is 0<y<pi, right?

anonymous
 one year ago
Best ResponseYou've already chosen the best response.0Yes, I actually based my answer on the unit circle. My answer is \[\frac{ \pi }{ 6 }\]

campbell_st
 one year ago
Best ResponseYou've already chosen the best response.1here is a triangle dw:1437262431290:dw so the cosine of which angle is \[\cos(?) = \frac{\sqrt{3}}{2}\]

anonymous
 one year ago
Best ResponseYou've already chosen the best response.0right @campbell_st ?

campbell_st
 one year ago
Best ResponseYou've already chosen the best response.1you just need to remember the exact value triangles... I always think about the longest side is opposite the largest angle 2 = 90 1 = 30 shortest and smallest angle

anonymous
 one year ago
Best ResponseYou've already chosen the best response.0@campbell_st Oh, I don't that one. It is Geometry. Thanks for the help! :)

campbell_st
 one year ago
Best ResponseYou've already chosen the best response.1it is a property from geometry that can be applied to any triangle.. so its handy to know for trig... seeing trig is about triangle measurements
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