a) 4/15
b) 15/4
c) 1/2
d) 11/20
2007-01-16 19:26:43 · 7 answers · asked by Anonymous in Science & Mathematics ➔ Mathematics
b) 15/4
You should write the brackets right:
f(x) = (4x² - 1) / x²
f(-2) = (16-1)/4 = 15/4
2007-01-16 19:50:34 · answer #1 · answered by anton3s 3 · 1⤊ 0⤋
F(-2)=4*-2^2 - 1/-2^2
=16-1/4
=15/4
2007-01-17 02:00:35 · answer #2 · answered by SNK 1 · 1⤊ 0⤋
f(x) = 4x^2 - 1 / x^2
f(-2) = 4*4 - 1 / 4
= 16-1 /4
=15/4
hence, (b) is the answer.
2007-01-16 20:19:28 · answer #3 · answered by arunima 2 · 1⤊ 0⤋
Please use parenthesis and/or brackets. Do you mean
f(x) = (4x^2-1)/(x^2)?
First: the problem gives you the value for "x" > replace "x" with
- 2...
f(- 2) = [4(-2)^2-1]/[(-2)^2]
Sec: solve according to order of operations > PEMDAS > >>
( ), exponents, multiplication, division, addition & subtraction...
f(- 2) = [4(4)-1]/4
f(- 2) = [16 - 1]/4
f(- 2) = 15/4
2007-01-17 03:42:02 · answer #4 · answered by ♪♥Annie♥♪ 6 · 0⤊ 0⤋
I guess that you mean (4x^2-1)/x^2
(-2)^2 = -2 * (-2) = 4. Remember: (-) * (-) = +
The numerator is 4*4 - 1 = 15
And the numerator is 4
So, the right answer is b
And
2007-01-16 19:53:51 · answer #5 · answered by MathTutor 6 · 0⤊ 0⤋
f(x)=4x^2-1/x^2
f(-2)
= 4(-2)^2-1/(-2)^2
= 4 *4 -1/4
= 16 - 1/4
= 63/4 or 15.75
2007-01-16 19:38:47 · answer #6 · answered by Kinu Sharma 2 · 0⤊ 1⤋
definitely answer (b)
Sequence of solving math problems as follow:
1: powers of
2: multiply or divides
3: Adding or subtraction
;)
2007-01-16 19:58:51 · answer #7 · answered by aldandooon 1 · 0⤊ 0⤋