2. Questions Bank
  3. 8th Class
  4. Mathematics
  5. Factorisation

8th Class Mathematics Factorisation Question Bank Factorisation

  • question_answer
    For \[{{x}^{2}}+2x+5\] to be a factor of\[x4+p{{x}^{2}}+q\], the values of p and q must be _____.

    A)  -2, 5               

    B)  5, 25  

    C)  10, 20            

    D)  6, 25  

    Correct Answer: D

    Solution :

    \[:{{x}^{2}}+2x+5\] be a factor of \[{{x}^{4}}+p{{x}^{2}}+q\] So, other be \[{{x}^{2}}-2x+5\] So \[({{x}^{2}}-2x+5)({{x}^{2}}+2x+5)\] \[={{({{x}^{2}}+5)}^{2}}-4{{x}^{2}}={{x}^{4}}+10{{x}^{2}}+25-4{{x}^{2}}\] \[={{x}^{4}}+6{{x}^{2}}+25\] So, \[p=6,\] \[q=25\]


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