Site icon Noon Academy

If cos 9α = sinα and 9α < 90°, then the value of tan5α is

(A) 1/√3 (B) √3 (C) 1 (D) 0

(C) 1

As indicated by the inquiry,

   

for example 9α is an intense point

We realize that,

   

In this way,

   

Since,

   

Subsequently, sin (90°-9∝) = sin∝

   

10∝ = 90°

∝ = 9°

Subbing ∝ = 9° in tan 5∝, we get,

   

∴, tan 5∝ = 1