MHT CET202520 Apr 2025Evening ShiftMathematicsApplication of DerivativesActual
If the curve y=a x^2-6 x+b passes through (0,4) and has its tangent parallel to the x -axis at x= 3 2 , then the value of a and b respectively are
Options
- A-2,-4
- B2, 4
- C-2,4
- D2,-4
Correct answer
B. 2, 4
Step-by-step solution
The curve y=ax^2-6x+b passes through the point (0,4) , so substituting gives 4=a(0)^2-6(0)+b , which simplifies to b=4 . Since the tangent is parallel to the x-axis at x= 3 2 , the derivative dy dx =2ax-6 must be zero at that point. Setting 2a 3 2 -6=0 yields 3a-6=0 , so a=2 . The values are therefore a=2 and b=4 , corresponding to option B .