Question

subtract 3a^2-4ab+7b^2 from (a-b)(a+b)​

Answer 1

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subtract 3a^2-4ab+7b^2 from (a-b)(a+b)

$\huge\tt{\bold{\underline{\underline{Answer᎓}}}}$

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$Substract = > 3 {a}^{2} - 4ab + 7 {b}^{2} ...(1)$

$from \: (a + b)(a - b)$

FORMULA:-

$\bold{\boxed{(a + b)(a - b) = {a}^{2} - {b}^{2}}}$....(2)

Now , Subtracting Equation1 from Equation2

$= > {a}^{2} - {b}^{2} - (3 {a}^{2} - 4ab + 7 {b}^{2} )$

$= > {a}^{2} - {b}^{2} - 3 {a}^{2} + 4ab - 7 {b}^{2}$

=>separating like terms together:-

$= > {a}^{2} - 3 {a}^{2} - {b}^{2} - 7 {b}^{2} + 4ab$

$= > - 2 {a}^{2} - 8 {b}^{2} + 4ab$

=>taking -2 common

$= > - 2( {a}^{2} + 4 {b}^{2} + 2ab)$

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