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If a - b = 3 and a² + b² = 29, find the value of ab = ?

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Answer:- 1

Explanation:-

Solution:

\begin{aligned} 2 a b \\ = (a^{2} + b^{2}) - {(a - b)}^{2} \\ = 29 - 9 = 20 \\ ∴ a b = 10 \end{aligned}

$\eqalign{ & 2ab \cr & = \left( {{a^2} + {b^2}} \right) - {\left( {a - b} \right)^2} \cr & = 29 - 9 = 20 \cr & \therefore ab = 10 \cr}$

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", "dateCreated": "7/24/2019 10:09:12 AM", "author": { "@type": "Person", "name": "Nitin Sir" } }, "suggestedAnswer": { "@type": "Answer", "text": "

Solution:

\begin{aligned} 2 a b \\ = (a^{2} + b^{2}) - {(a - b)}^{2} \\ = 29 - 9 = 20 \\ ∴ a b = 10 \end{aligned}

$\eqalign{ & 2ab \cr & = \left( {{a^2} + {b^2}} \right) - {\left( {a - b} \right)^2} \cr & = 29 - 9 = 20 \cr & \therefore ab = 10 \cr}$ ", "dateCreated": "7/24/2019 10:09:12 AM" } }

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