Question

If a is inversely proportional to √b and a = 6 when
b= 4what is the value of b when a = 4.​

Answer 1

The value of b is 9 when a = 4.

If a is inversely proportional to √b and a = 6 when b = 4.

We have to find the value of b when a = 4.

A/C to question,

a is inversely proportional to √b.

$\implies a=\frac{k}{\sqrt{b}}$

where k is proportionality constant.

given, a = 6 when b = 4.

∴ 6 = k/√(4)

⇒6 = k/2

⇒k = 12

hence equation is..

$\implies a=\frac{12}{\sqrt{b}}$

now, a = 4

$\implies4=\frac{12}{\sqrt{b}}$

$\implies\sqrt{b}=\frac{12}{4}=3$

$\implies b=9$

Therefore the value of b is 9.

Answer 2

It vary inversely

$b = 4 \\ \sqrt{b = 2}$

so, 4×L = 6×2

L = 6×2

_____ = 3

4

$3 = \sqrt{b \\ \: \\ \\ } \\ \\ b = 3$

b= 9