Question

Find the linear approximation at x=0 to 1/√(3−x). Write your answer in the form y=Ax+B.

Answer 1

1/root(5-x) = 1/(root5 * root 1- x/5)
1/root5 * (1-x/5)^-1/2

Using the 1st 2 terms of the binomial expansion 1 +nx:
1/root5 ( 1 + x/10)
= X/10root5 + 1/root5