Online Course Discussion Forum

Summer II A AMC 10 prep Question 3.22+3.23

 
 
GaoAndrew的头像
Summer II A AMC 10 prep Question 3.22+3.23
GaoAndrew - 2017年06月24日 Saturday 08:39
 

Does anyone remember the trick for doing 3.22 and 3.23 with the 1/x1 + 1/x2 , and x2,1 + x2,2?

 
ReynosoDavid的头像
Re: Summer II A AMC 10 prep Question 3.22+3.23
ReynosoDavid - 2017年06月25日 Sunday 21:15
 

Hey Andrew!

Remember you can always watch again the recording of the classes by using the same link that takes you to the live class.

Also, here's a hint for those problems: Remember that Viete's theorem tells you precisely what is the sum of the roots of an equation and also the product of the roots by just looking at the coefficients of a polynomial; also $(x_1+x_2)^2 = x_1^2 + 2x_1x_2 +x_2^2$ (Note that this expression involves the sum of the roots and also the product of the roots!).