Question

What is wrong with this answer/ where is the error?

Answer 1

we are given with b(t) =
`\sqrt{ t^(2) + 4 }`. when b (t^2), we replace t inside the square root with t^2. Hence the equation becomes
`\sqrt{ t^(4) + 4 }`. The error in the answer given is not replacing t with t^2 and separating the terms inside the square root which should not be the case.