MHT CET202527 Apr 2025Evening ShiftMathematicsContinuity and DifferentiabilityActual
If f (x)= cases -2 x & , x - 2 a x+ b & , - 2 < x < 2 x & , x 2 cases is continuous at x = - 2 and x= 2 , then the value of 2 a+ b is
Options
- A(0, -13 5 , 2 5 )
- B(0, 13 5 , 2 5 )
- C(0, 13 5 , 2 )
- D(0, -13 5 ,-2 )
Correct answer
A. (0, -13 5 , 2 5 )
Step-by-step solution
For f(x) to be continuous at x = - 2 and x = 2 , the left and right limits must equal the function values at these points. At x = - 2 , the left limit is 2 and the right limit is -a + b , yielding -a + b = 2 . At x = 2 , the left limit is a + b and the right limit is 0 , giving a + b = 0 . Solving this system, 2b = 2 so b = 1 , and a = -1 . Thus 2a + b = -2 + 1 = -1 . Final answer: -1