Question #6c32c

1 Answer
Feb 6, 2018

#x_1=1# and #x_2=1/3#

Explanation:

We want to find the horizontal tangent on the function

#f(x)=2x^3-4x^2+2x-3#

The graph must have a horizontal tangent when #f'(x)=0#

Differentiate the function by the power rule

#f'(x)=6x^2-8x+2#

Solve the quadratic equation #f'(x)=6x^2-8x+2=0#

#x=(8+-sqrt((-8^2)-4*6*2))/12#

#=(8+-4)/12#

#=(2+-1)/3#

The graph have a horizontal tangent at #x_1=1# and #x_2=1/3#