Q. 34.0( 4 Votes )

# Evaluate:

(i) (95)^{3}

(ii) (999)^{3}

Answer :

(i) We know that,

(a – b)^{3} = a^{3} – b^{3} – 3ab (a – b)

Using this formula, we get

= (100 – 5)^{3}

= (100)^{3} – (5)^{3} – 3 × 100 × 5 (100 – 5)

= 1000000 – 125 – (1500 × 95)

= 857375

(ii) We know that,

(a – b)^{3} = a^{3} – b^{3} – 3ab (a – b)

Using this formula, we get

= (1000 – 1)^{3}

= (1000)^{3} – (1)^{3} – 3 × 1000 × 1 (1000 – 1)

= 1000000000 – 1 – 3000 (1000 – 1)

= 1000000000 – 1 – 3000 × 1000 +3000 ×1

= 997002999

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75×75+2×75×25+25×25 equal to

RD Sharma - MathematicsIf x+ =5, then *x*^{2}+=

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Factorize:

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