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If a ∫ 0 3 X 2 D X = 8 , Write the Value of A. - Mathematics

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Question

If \[\int\limits_0^a 3 x^2 dx = 8,\] write the value of a.

 

 

Solution

\[\text{We have}, \]
\[ \int_0^a 3 x^2 d x = 8\]
\[ \Rightarrow \left[ 3\frac{x^3}{3} \right]_0^a = 8\]
\[ \Rightarrow \left[ x^3 \right]_0^a = 8\]
\[ \Rightarrow a^3 - 0 = 8\]
\[ \Rightarrow a = \sqrt[3]{8}\]
\[ = 2\]

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Definite Integrals
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Chapter 20: Definite Integrals - Very Short Answers [Page 116]

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RD Sharma Mathematics [English] Class 12
Chapter 20 Definite Integrals
Very Short Answers | Q 32 | Page 116

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