Question

evaluation (70+1)²=_____________​

Answer 1

(a+b)² = a²+2ab+b²

(70+1)²= (70)²+2×70×1+(1)²

(70+1)²=4900+140+1

(70+1)²=5041

Answer 2

Question:-

Evaluatie (70+1)²

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Solution:-

Usind identity

$\green{\bf{( a + b )² = a² + 2ab + b²}}$

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Here,

a = 70;b = 1

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$\pink{\bf{( 70 + 1 )²}}$

$\pink{\bf{= 70² + (2×70×1) + 1²}}$

$\pink{\bf{= 4900 + 140 + 1}}$

$\pink{\bf{= 5041}}$

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Identity to be remembered:-

▪︎$\blue{\bf{( a + b )² = a² + 2ab + b²}}$

▪︎$\blue{\bf{( a - b )² = a² - 2ab + b²}}$

▪︎$\blue{\bf{a² - b² = ( a + b ) ( a - b )}}$