COMEDK2024Morning ShiftMathematicsLimitsActual
_ x 0 a+x - a x a(a+x) equals to
Options
- A1 2
- Ba^ - 3 2
- C2 a^ - 3 2
- D1 2 a^ 3 2
Correct answer
D. 1 2 a^ 3 2
Step-by-step solution
Let the given limit be L = _ x 0 a+x - a x a(a+x) . Rationalizing the numerator by multiplying and dividing by ( a+x + a ) : L = _ x 0 ( a+x - a )( a+x + a ) x a(a+x) ( a+x + a ) L = _ x 0 (a+x) - a x a(a+x) ( a+x + a ) L = _ x 0 x x a(a+x) ( a+x + a ) L = _ x 0 1 a(a+x) ( a+x + a ) Substituting x = 0 into the expression: L = 1 a(a+0) ( a+0 + a ) L = 1 a^2 ( a + a ) L = 1 a(2 a ) L = 1 2 a a^ 1 2 = 1 2 a^ 3 2 Answer: 1 2 a^ 3 2