Question

2.
Find the domain of f(x) = sin-1(x² + 2x + 4).​

Answer 1

Answer:

Correct option is

C

{−1,1}

f(x)=sin

−1

(

2x

1+x

2

)=sin

−1

[

2

1

(x+

x

1

)]

we know

∣

∣

∣

∣

∣

∣

x+

x

1

∣

∣

∣

∣

∣

∣

≥2 and sin

−1

x only exist if −1≤x≤1

⇒ This in only possible if x=−1or1

Hence domain of f(x) is {−1,1}