Q1 of 105 Page 280

Find the errors and correct the following mathematical sentences

(2a + 3)2 = 2a2 + 6a + 9

If LHS is


(2a + 3)2


Then RHS would be


⇒ (2a + 3)2


= (2a)2 + 32 + 2 × 2a × 3


= 4a2 + 9 + 12a


= 4a2 + 12a + 9


The error is 4a2 instead of 2a2 and 12a instead of 6a


Hence = (2a + 3)2 = 4a2 + 9 + 12a


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