Example 4 class 10th

Example:- Find the root of the quadratic equation 6x2-x-2=0

Solution:- we have

6x2-x-2= 6x2+3x-4x-2

            =3x(2x+1)-2(2x+1)

            =(3x-2)(2x+1)

The roots of 6x2-x-2=0 are the values of x for which (3x-2)(2x+1)=0

Therefore, 3x-2=0 or 2x+1=0

i.e, 3x=2 or 2x=-1

      x=2/3 or x=-1/2

Therefore, the roots of 6x2-x-2=0 are 2\3 and -1\2



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