8th Class Mathematics Algebraic Expressions Question Bank Algebraic Expressions and Identities

  • question_answer
    What is the product of \[(4x-3y)\] and \[(16{{x}^{2}}+12xy+9{{y}^{2}})\]?

    A)  \[{{(4x-3y)}^{3}}\]

    B)  \[{{(16{{x}^{2}}+12xy+9{{y}^{2}})}^{2}}\]

    C)  \[64{{x}^{3}}-27{{y}^{3}}\]

    D)  \[64{{x}^{3}}+27{{y}^{3}}\]

    Correct Answer: C

    Solution :

    \[(4x-3y)\,(16{{x}^{2}}+12xy+9{{y}^{2}})\] \[=(4x-3y)\,(16{{x}^{2}}+12xy+9{{y}^{2}})\] \[=(4x)\,(16{{x}^{2}}+12xy+9{{y}^{2}})\]                 \[+(-3y)\,(16{{x}^{2}}+12xy+9{{y}^{2}})\] \[=64{{x}^{3}}+48{{x}^{2}}y+36x{{y}^{2}}\]                \[-48{{x}^{2}}y-36x{{y}^{2}}-27{{y}^{3}}\] \[=64{{x}^{3}}-27{{y}^{3}}\]


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