EasyCalculusca-252

Newton Step for the Square Root

Problem

One Newton step for computing the square root of a solves z^2 - a = 0 and gives z_new = z - (z^2 - a) / (2z).

Given a > 0 and a nonzero current estimate x, return the updated estimate.

Hint

The update averages the estimate with a / x, which converges quadratically.

case 1

in: [2,1]

expected: 1.5

case 2

in: [4,2]

expected: 2

case 3

in: [9,2]

expected: 3.25

case 4

in: [1,1]

expected: 1

Starter codePython

def newton_sqrt_step(a, x):
    # Your code here
    pass

4 test cases · run your code against them in the editor