Question

if sin theta equals to 3/5 show that cos square theta minus sin square theta by cos theta equals to 1 minus tan squared theta by sec theta

Answer 1

Answer:

Let theta = x

sin x= -3/5 , 180° < x < 270°

cos x=×/-(1-sin^2x)^1/2 = +/-(1–9/25)^1/2

cos x = -4/5 (x lies in 3rd quadrant )

Now

tan x = sin x/cos x = (-3/5)÷(-4/5) = 3/4 .

sec x = 1/cos x = 1/(-4/5) = -(5/4) , Answer