# precalculus

2. Simplify (8x^6 times 32y^5)^(1/2)

3. Approximate the real zeros of f(x)= 2x^4 + 3x^2 - 20.

1. 👍 0
2. 👎 0
3. 👁 108
1. Let u = x^2 and solve
2u^2 -3u -20 = 0

That can be factored, to give
(2u +5)(u-4) = 0
u = 4 OR -5/2
x = sqrt4 or sqrt(-3/2)

The only REAL zeros are +2 and -2

1. 👍 0
2. 👎 0
posted by drwls

## Similar Questions

1. ### Math

f(x)=x64-4x^2+k. Find the values of k so thath the zeros of f satisfy the specified charachteristics. a.four real zeros b.two real zeros, each of multiplicity of two c.two real zeros and two complex zeros d.four complez zeros a.I

asked by Anonymous on January 19, 2015

Find the number of possible negative real zeros for f(x)=6+x^4+2x^2-5x^3-12. Answer: 0 2) Approximate the real zeros of f(x)=2x^4-3x^2-2 to the nearest tenth. Answer: no real roots

asked by Lucy on August 31, 2008

Find the number of possible negative real zeros for f(x)=6+x^4+2x^2-5x^3-12. Answer: 0 2) Approximate the real zeros of f(x)=2x^4-3x^2-2 to the nearest tenth. Answer: no real roots

asked by Lucy on August 30, 2008

Find the number of possible negative real zeros for f(x)=6+x^4+2x^2-5x^3-12. Answer: 0 2) Approximate the real zeros of f(x)=2x^4-3x^2-2 to the nearest tenth. Answer: no real roots

asked by David on March 26, 2009
5. ### pre-calculus

Find the number of possible negative real zeros for f(x)=6+x^4+2x^2-5x^3-12. Answer: 0 2) Approximate the real zeros of f(x)=2x^4-3x^2-2 to the nearest tenth. Answer: no real roots

asked by lucy on August 27, 2008

Find the number of possible negative real zeros for f(x)=6+x^4+2x^2-5x^3-12. Answer: 0 2) Approximate the real zeros of f(x)=2x^4-3x^2-2 to the nearest tenth. Answer: no real roots

asked by Lucy on August 23, 2008
7. ### calculus

Determine which consecutive integers the real zeros of the function are located. f(x) = 4x^4 - 16x^3 - 25x^2 + 196x -146 Is there an easier way to this besides trial and error synthetic division? Also, how do I approximate the

asked by Christy on August 12, 2010
8. ### rational zeros theorem

Use the rational zeros theorem to find all the real zeros of the polynomial function. Use the zeros to factor f over the real numbers. f(x)=25x^4+26x^3+126x^2+130x+5 Find the real zeros x= Use the real zeros to factor f f(x)=

asked by Jill on April 9, 2013
9. ### College algebra

Use the rational zeros theorem to find all the real zeros of the polynomial function. Use the zeros to factor f over the real numbers f(x)=9x^4+28x^3+66x^2+196x+21 Find the real zeros of f Use the real zeros to factor f f(x)=

asked by Alex on May 14, 2013
10. ### algebra

Could you help me with this? find the real zeros of f(x) = x^3-8^2+9x+18(x-8^2+9x+18 I know it must be real simple. I have a block somewhere. Thanks I think I understand the Descartes rule of sign change. This equation has 2 sign

asked by Dee on March 19, 2010

More Similar Questions