A basic question from factorisation chapter in which we are asked to prove that (x – 2) is a factor of 3x2−x−10. It means ultimately we have to factories 3x2−x−10
ML Aggarwal Avichal Publication, Factorisation, chapter 6, Question no 10
Share
Lost your password? Please enter your email address. You will receive a link and will create a new password via email.
Consider g(x)=0⇒x−2=0⇒x=2
Now putting x=2 in p(x), We get
p(2)=3(2)
2
−(2)−10
=12−2−10=0
∴ By factor theorem, (x−2) is a factor of p(x)
Hence proved.
Now, 3x
2
−x−10
=3x
2
−6x+5x−10
=3x(x−2)+5(x−2)
=(x−2)(3x+5)