precalculus
posted by Tiana .
1. Express (3x)^(1/5)(3x^2)^(1/3) using radicals
2. Simplify (8x^6 times 32y^5)^(1/2)
3. Approximate the real zeros of f(x)= 2x^4 + 3x^2  20.

Let u = x^2 and solve
2u^2 3u 20 = 0
That can be factored, to give
(2u +5)(u4) = 0
u = 4 OR 5/2
x = sqrt4 or sqrt(3/2)
The only REAL zeros are +2 and 2