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If 4A2+B2=244A^2+B^2=244A2+B2=24​ and AB = 4, find the value of 2A+B.
Question

If 4A2+B2=244A^2+B^2=24​ and AB = 4, find the value of 2A+B.

A.

±3√5

B.

±2√5

C.

±2√10

D.

±3√10

Correct option is C

Given:
4A2+B2=244A^2 + B^2 = 24​​
AB = 4
Formula Used:
(2A+B)2=4A2+B2+4AB(2A + B)^2 = 4A^2 + B^2 + 4AB​​
Solution:
Substitute the given values into the identity:
(2A+B)2=24+4×4(2A + B)^2 = 24 + 4 × 4​​

(2A+B)2=24+16=40(2A + B)^2 = 24 + 16 = 40​​

2A+B=±40=±2102A + B = \pm\sqrt{40} = \pm2\sqrt{10}​​
Final Answer
So the correct answer is (c)

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