AP EAMCET201822 Apr 2018Evening ShiftMathematicsApplication of DerivativesActual
On the curve y=x^3 , the point at which the tangent line is parallel to the chord joining the points (-1,-1) and (2,8) is
Options
- A(1, - 1)
- B(2, 8)
- C(1, 1)
- D(3, 27)
Correct answer
C. (1, 1)
Step-by-step solution
According to Lagrange's Mean value theorem, y=x^3 is a continuous and differentiable function So, there exist x= c , such that f^ (c)= f(2)-f(-1) 2-(-1) aligned & & 3 c^2 & = 8-(-1) 3 =3 c^2=1 & & c & = 1 aligned So, point is (1,1) .