How do you differentiate sqrtt*(1-t^2)?

1 Answer
May 19, 2015

It's quickest to multiply \sqrt{t} through with the distributive property and then use linearity and the power rule:

d/dt(\sqrt{t}\cdot (1-t^{2}))=d/dt(t^{1/2}-t^{5/2})=\frac{1}{2}t^{-1/2}-\frac{5}{2}t^{3/2}.

For extra fun, you can also use the product rule along with linearity and the power rule:

d/dt(\sqrt{t}\cdot (1-t^{2}))=\frac{1}{2}t^{-1/2}(1-t^{2})+t^{1/2}\cdot (-2t)

=\frac{1}{2}t^{-1/2}-\frac{1}{2}t^{3/2}-2t^{3/2}=\frac{1}{2}t^{-1/2}-\frac{5}{2}t^{3/2}.