m2 – 3m – 10 = 0


(i) m2 – 3m – 10 = 0
Sol. m2 – 3m – 10 = 0
Comparing with am2 + bm + c = 0 we have a = 1, b = –3, c = –10
b2 – 4ac = (– 3)2 – 4 (1) (–10)
= 9 + 40
= 49
By Formula method,
m
=
-  b ± √(b2 – 4ac)




2a







∴ m
=
-(-3)± √49




2(1)







∴ m
=
3 ± 7




2







∴ m
=
3+7
or
3-7


2

2





∴ m
=
10
or
-4


2

2





∴ m
=
5
or
-2