by tza5021
 P: 5 f(x) = –3√x, 1 ≤ x ≤ 4 (a) Find the quadratic least squares approximating function g for the function f. g(x)=?
 Sci Advisor HW Helper Thanks P: 25,235 The best fit function is clearly g(x)=-3/sqrt(x). But I'm guessing you trying to fit a function that's doesn't have that form. What kind of function are you trying to fit and what's the definition of 'least squares fit'?
 P: 5 Using g(x)= a0+a1x+a2x^2 when 1
 P: 5 Quadratic least squares equation If you could help that would be very much appreciated as I do not knw how to punch and chug that in an intergral.
HW Helper
Thanks
P: 25,235
 Quote by tza5021 If you could help that would be very much appreciated as I do not knw how to punch and chug that in an intergral.
I think you want to minimize the integral of (f(x)-g(x))^2 don't you? Put in your f(x) and your g(x). It's not a hard integral. Just square it out. It's just powers of x. Then try to minimize with respect to a0, a1 and a2.
 P: 5 How do I minimize the a0,a1 and a2 I do not get that part
HW Helper
Thanks
P: 25,235
 Quote by tza5021 How do I minimize the a0,a1 and a2 I do not get that part
Use partial derivatives with respect to a0, a1 and a2. What should they be at a minimum? Didn't they teach you that part?
 P: 5 Yes, but I missed the class. So could you tell me how to do that