^2+ .b ^2=144 and =4 then is equal to: - Vidyadip

MCQ

$\mid\text{a}\times\text{b}\mid^2+\mid\text{a.b}\mid^2=144$ and $\mid\text{a}\mid=4$ then $\mid\text{b}\mid$ is equal to:

A
$12$
✓
$3$
C
$8$
D
$4$

✓

Answer

Correct option: B.

$3$

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