Question
Mathematics Question on limits and derivatives
x→2lim [x−21−x3−3x2+2x2(2x−3)] is equal to
A
−21
B
21
C
0
D
∞
Answer
−21
Explanation
Solution
We have, x→2lim [x−21−x3−3x2+2x2(2x−3)] =x→2lim [x−21−x(x−1)(x−2)2(2x−3)] =x→2lim [x(x−1)(x−2)x(x−1)−2(2x−3)] =x→2lim [x(x−1)(x−2)x2−5x+6] =x→2lim [x(x−1)(x−2)(x−2)(x−3)] =x→2lim [x(x−1)(x−3)]=2−1