The equation (a + b)^2 = 4ab , ^2 is possible only when - Vidyadip

MCQ

The equation ${(a + b)^2} = 4ab\,{\sin ^2}\theta $ is possible only when

A
$2a = b$
✓
$a = b$
C
$a = 2b$
D
None of these

✓

Answer

Correct option: B.

$a = b$

b
(b) We have ${(a + b)^2} = 4ab{\sin ^2}\theta $

$ \Rightarrow {\sin ^2}\theta = \frac{{{{(a + b)}^2}}}{{4ab}} \le 1 $

$\Rightarrow {(a + b)^2} - 4ab \le 0$

$ \Rightarrow {(a - b)^2} \le 0 $

$\Rightarrow a = b.$

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