4m2 – 9 = 0, m = 2, 2/3, 3/2


(ii) 4m2 – 9 = 0, m = 2, 2/3, 3/2

Sol. a) By putting m = 2 in L.H.S. we get

L.H.S. = 4(2)2 – 9

= 4(4) – 9

= 16 – 9

= 7

R.H.S.

 L.H.S. R.H.S.

Thus equation is not satisfied.

So, 2 is not the root of the given quadratic equation.



b) By putting m = 2/3 in L.H.S. we get

L.H.S. = 4(2/3)2 – 9

= 4(4/9) – 9

= (16/9 )- 9

= (16 – 81)/9

= - 65 / 9

≠ RHS

∴  L.H.S. ≠ R.H.S.

Thus equation is not satisfied.

So, 2/3 is not the root of the given quadratic equation.



c) By putting m = 3/2 in L.H.S. we get

L.H.S. = 4(3/2)2 – 9

= 4(9/4) – 9

= 9 – 9

= 0

= R.H.S.

 L.H.S. = R.H.S.

Thus equation is satisfied.


So, 3/2 is the root of the given quadratic equation.