Use a sketch to find the exact value of the expression cossi

Use a sketch to find the exact value of the expression. cos(sin^-1(3/5)) A. 1/5 B. 4/5 C. - 3/5 D. - 4/5

Solution

cos(sin^-1(3/5))

Let sin^-1(3/5)=t

sin t=3/5

Here adjacent =3   and hypotenuse=5

opposite=sqrt(5²-3²)=4

cos t= 4/5

Therefore cos (sin^-1(3/5))=4/5

Correct answer is B