Can someone help me find the value of Sin X and Cos Y? What relationships do the rations of cos Y and sin X share?

Question

Answer 1

Evaluation of both the sine and cosine function require knowing the length of the hypotenuse. In this case that can be found using the Pythagorean theorem.

c² = a² + b² (where c is the hypotenuse)

c² =3² + 4²

c² =25

c = 5

sin(x) = opp./ hyp.

sin(x) = 3/5

cos(y) = adj./hyp.

cos(y) = 3/5

The special relationship between sine and cosine is that sine of any angle is equal to the cosine of that angle's complement and vice versa.

Answer 2

Hi,

first, you know the definition of sin and cos

second, you know the relation between sides and hypotenuse of right angle hypo²= 3^2 + 4^2 = 25 ==>

hypo =5

Third,

sin x = opposite/ hypotenuse = 3/5

cosy = adjacent / hypotenuse = 3/5

Fourth, you see the same answer, so you need to make a result that when x and y are complementary angles so

sin x = cos y or cos x = sin y

I hope it is useful,

Minoo