RRB Group D Model Paper 6 with solutions

© examsiri.com

Question : 55 of 99

Marks: +1, -0

If

{tanθ + cotθ}/ {tanθ - cotθ}

= 2, (0 ≤ θ ≤ 90°), then the value of sin θ is

$2/√3$
$√3/2$
$1/2$
1

Solution:

(2)

{tanθ + cotθ}/ {tanθ - cotθ}

= 2
By Componendo and dividendo
⇒

{tanθ+ cotθ+ tanθ -cotθ}/ {tanθ+ cotθ- tanθ+ cotθ }={2+1}/{2-1}

⇒

{2tanθ} / {2cotθ}= 3/1

⇒

{sin^2θ}/ {cos^2θ}= 3/1

⇒

sin^2θ

= 3(1-

sin^2θ

)
⇒ Therefore,

sin^2θ=3/4

⇒ sinθ =

√3/2

© examsiri.com

Go to Question:

Prev Question

Next Question