10x^4-9x^2+2=0
first factor to
(2x^2 - 1)(5x^2 - 2) = 0
x^2 = 1/2 or x^2 = 2/5
x = ±1/√2 or x = ±√2/√5
your text answer might have these rationalized.
(2x^2 - 1)(5x^2 - 2) = 0
x^2 = 1/2 or x^2 = 2/5
x = ±1/√2 or x = ±√2/√5
your text answer might have these rationalized.