Question

If sinx=4/5 what is cos(90-x)

Answer 1

The cosine of the complement of x, cos(90-x), equals the sine of x, so cos(90-x) is 4/5 given that sinx = 4/5.

Step-by-step explanation:

If we have sinx = 4/5, we can find cos(90-x) by applying a fundamental trigonometric identity. We know that sin of an angle is the same as the cos of its complement. Therefore, if sinx is 4/5, then cos(90-x) will also be 4/5. This follows from the identity sin(x) = cos(90°-x).

Answer 2

sin(x) = ⁴/₅
sin⁻¹[sin(x)] = sin⁻¹(⁴/₅)
x ≈ 53.13

cos(90 - x) = cos(90)cos(x) + sin(90)sin(x)
cos(90 - 53.13) = cos(90)cos(53.13) + sin(90)sin(53.13)
cos(36.87) = 0cos(53.13) + sin(53.13)
cos(36.87) = sin(53.13)
cos(36.87) = cos(90 - 53.13)
cos(36.87) = cos(36.87)