Question

4.
If a cos 0 + b sin 0 = 3 and a sin 0 - 6 cos 0 = 4
then the value of a2 + b2 is
(A) 9
(B) 16
(C) 25
(D) none of these​

Answer 1

Heya mate ...

Here is your answer .....

a cos 0 + b sin 0 = 3

since cos 0 is 0 and sin 0 is 1 substitute in the above equation..

Then , a(0) + b(1) = 3

b = 3

and ...

a sin 0 - 6 cos 0 = 4

a = 4

so , here 'a' value is 4 and `b' value is 3 .

The given equation is 2a + 2b

substitute a and b values in 2a + 2b

Then , 2 ( 4 ) + 2 ( 3 )

= 8 + 6

= 14

so , option is D ) None of these

Hope it helps you ..

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