Q1 of 105 Page 280

Find the errors and correct the following mathematical sentences

(x + 7)2 = x2 + 49

If LHS is


(x + 7)2


Then RHS would be


⇒ (x + 7)2


= (x)2 + 72 + 2 × x × 7


= x2 + 49 + 14


The error is x2 + 14x + 49 instead of x2 + 49


Hence (x + 7)2 = x2 + 14x + 49


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