Question

Suppose that sin @= 5/13 and @ is in quadrant 2.
A. Find the exact value of cos@
B. Find the exact value of sin 2@

Answer 1

Remember SOH-CAH-TOA
sin cos tan

sin(Theta) or sin(Angle) = Opposite/Hypotenuse
cos(Theta) = Adjacent/Hypotenuse
tan(Theta) = Opposite/Adjacent

Answer 2

sin(theta)=5/13
that represents the hypotenuse = 13 and the side opposite (the vertical side) = 5
got this?
so the adjacent side is=(-12)
so now can u calculate cos(theta)

Answer 3

We say Theta to represent the angle.

When you said sin@ , what the @ sign is - is the angle
So we we say the sin(Theta) we are saying the sin(of the angle) or in your case the sin@

If we know that the sin@ = Opposite / Hypotenuse
And you are saying that the sin@ = 5/13

@sidsiddhartha is saying that 5 will be the opposite side and the 13 will be the hypotenuse.

This refers to a triangle where