SOLUTION: 15x^4-11x^2+2=0

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Question 975114: 15x^4-11x^2+2=0
Answer by josgarithmetic(39617) About Me  (Show Source):
You can put this solution on YOUR website!
Try using v=x^2 and first solve for v.

15v%5E2-11v%2B2=0
If factorable, then easier to finish:

%283v-1%29%285v-2%29=0

ZERO PRODUCT RULE & REVERSE SUBSTITUION:
3v-1=0
3v=1
v=1%2F3
x%5E2=1%2F3
x=0%2B-+sqrt%281%2F3%29
highlight%28x=0%2B-+sqrt%283%29%2F3%29

5v-2=0
5v=2
v=2%2F5
x%5E2=2%2F5
x%5E2=%282%2F5%29%285%2F5%29=10%2F5%5E2
highlight%28x=0%2B-+sqrt%2810%29%2F5%29