Q. 1 O4.0( 10 Votes )

# Find the errors and correct the following mathematical sentences

(3a + 4b) (a – b) = 3a^{2} – 4a^{2}

Answer :

For getting in the equation

(a^{2} – b^{2} ) = (a + b)(a-b)

RHS would be

3a^{2} – 4b^{2}

Then LHS would be

⇒ 3a^{2} – 4b^{2}

= (3a – 4b)(3a + 4b)

The error is (a – b) instead of (3a – 4b)

3a^{2} – 4b^{2} instead of 3a^{2} – 4a^{2}

Hence 3a^{2} – 4b^{2} = (3a – 4b)(3a + 4b)

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