If cos (x + 25)o = sin 45o, find the value of x

If cos (x + 25)^o = sin 45^o, find the value of x

Answer Details

We know that cos (90^o - A) = sin A. So, cos (x + 25^o) = cos (90^o - 45^o) = cos 45^o. Since cos A = cos B implies A = ±B + 360^on, we have: x + 25^o = ±45^o + 360^on x = -25^o ± 45^o + 360^on x = 20^o + 360^on or x = 70^o + 360^on Since we are given the range of x, we take x = 20^o. Therefore, the value of x is 20^o.