How do you differentiate f(x)= x/(4x-2) using the quotient rule?

1 Answer
Jan 26, 2016

f'(x)=-1/(2(2x-1)^2

Explanation:

f(x)=x/(4x-2)=1/2(x/(2x-1))

We could taking 2 at the denominator to make easy the computation

f'(x)=d/(dx)[1/2(x/(2x-1))]=1/2d/(dx)(x/(2x-1))=1/2d/(dx)i(x)

Now i(x)=(h(x))/g(x)

The Quotient Rule tells us:

given: i(x)=(h(x))/g(x)

i'(x)=(h'(x)*g(x)-g'(x)*h(x))/(g(x))^2

:.f'(x)=1/2[(1*(2x-1)-(2-0)*x)/(2x-1)^2]=

=1/2[(color(green)cancel(2x)-1color(green)cancel(-2x))/(2x-1)^2]=

=1/2*(-1/(2x-1)^2)=-1/(2(2x-1)^2