BITSAT2015MathematicsApplication of DerivativesActual
The number of real roots of the equation e e ^ (x-1) + x -2=0 is
Options
- A1
- B2
- C3 3
- D4
Correct answer
A. 1
Step-by-step solution
Let f(x)=e^ x-1 +x-2 check for x=1 Then, f (1)= e ⁰+1-2=0 So, x=1 is a real root of the equation f(x)=0 Let x= be the other root such that >1 or 0, for all x . Thus f ^ ( x ) 0, for any x (1, ) or x ( , 1) which is a contradiction. Hence, f ( x )=0 has no real root other than 1 .