Solving a Complex Equation: Finding wasym with Error

[zak8000]

Homework Statement

i am given an equation like this w_asym=sqrt[w_o²+gb/2L(L-b)]

where L=60.7 ± 0.4cm and b=L/5
g=9.789 ms^-2
w_o=4.001 ± 0.004 −1
and i am told to find the value for w_asym

i get for my 4.25 rads-1 but i don't know how to calculate the error on the back of my textbook it says the answer is 6.53%

with the following working
sqrt[0.1%^2 ( 0) + 6.5%^2 ( ) + 0.66%^2 ( )] = 6.53 % i don't understand how they got the answer any help would be appreicated

Homework Equations

The Attempt at a Solution

 

[ideasrule]

Do you have any knowledge of error analysis? Surely if you're being asked this question, you already learned about error propagation and had various formulas for addition, subtraction, powers, etc?