Question

I need help figuring this out.

If f(x)=x^1\2-x and g(x)=2x^3-x^1/2-x, find f(x)-g(x).

-2x^3-2x-2x^1/2
-2x^3-2x
2x^3-2x+2x^1\2
-2x^3+2x^1\2

Answer 1

Do as it is asking
\[f(x) - g(x)\]
We know\[f(x) = x^{1/2}-x\] and \[g(x) = 2x^3-x^{1/2}-x\]

So you must subtract g(x) from f(x) using those 2 equations.

Answer 2

How do you know if it's either subtraction, addition, multiplication or division. That's what confuses me.

Answer 3

It shows you in your original expression
\[f(x) - g(x)\]

It means to subtract g(x) from f(x)

Answer 4

Okay...
I just put it in the calculator and I got 2x^3-2x^1/2 but that's not one of the choices.

Answer 5

You were close,

Answer 6

You forget that you are subtracting so the first term is negative -2x^3

Answer 7

and the second turns positive

Answer 8

\[f(x) - g(x)\]
\[f(x) = x^{1/2} - x\]\[g(x) = 2x^3-x^{1/2}- x\]

So
\[x^{1/2}- x - (2x^3 - x^{1/2} - x)\]

You can see that they are all being subtracted so you get
\[x^{1/2} - x -2x^3 + x^{1/2}+x\]