JEE Main & Advanced Mathematics Definite Integration Question Bank Properties of Definite Integration

  • question_answer
    Let \[a,\,\,b,\,\,c\] be non-zero real numbers such that \[\int_{0}^{3}{(3a{{x}^{2}}+2bx+c)\,dx}=\int_{1}^{3}{(3a{{x}^{2}}+2bx+c})\,dx\,,\] then [BIT Ranchi 1991]

    A)                 \[a+b+c=3\]      

    B)                 \[a+b+c=1\]

    C)                 \[a+b+c=0\]      

    D)                 \[a+b+c=2\]

    Correct Answer: C

    Solution :

               \[\int_{0}^{3}{(3a{{x}^{2}}+2bx+c)dx=\int_{1}^{3}{(3a{{x}^{2}}+2bx+c)dx}}\]                    Þ \[\int_{0}^{1}{(3a{{x}^{2}}+2bx+c)dx+\int_{1}^{3}{(3a{{x}^{2}}+2bx+c)dx}}\]                                                           \[=\int_{1}^{3}{(3a{{x}^{2}}+2bx+c)dx}\]                    Þ \[\int_{0}^{1}{(3a{{x}^{2}}+2bx+c)dx=0}\]                                 Þ \[\left[ \frac{3a{{x}^{3}}}{3}+\frac{2b{{x}^{2}}}{2}+cx \right]_{0}^{1}=0\Rightarrow a+b+c=0\].


You need to login to perform this action.
You will be redirected in 3 sec spinner