Question

Did I solve these square root functions correctly?
& If not, what did I do wrong?
http://tinypic.com/view.php?pic=2wh1edc&s=6

Answer 1

f(x) = 4x - 1
g(x) = x^2 + 3
5. (f + g)(x)
(f + g)(x) =
f(x) + g(x) =
4x - 1 + x^2 + 3
You had it right up to here.
You can't add 4x and x^3 because they are not like terms. Like terms have exactly the same variable parts. For example 4x^2 + x^2 = 5x^2, but 4x^2 + x = 4x^2 + x. x^2 and x are not like terms.

Answer 2

In 6. you made the same error. You can only combine like terms. x^2 and x are not like terms.

Answer 3

so for 5 do i just add 3 and -1?

Answer 4

Right, bec 4x and x^2 can't be combined

Answer 5

5. (f + g)(x)
(f + g)(x) =
f(x) + g(x) =
4x - 1 + x^2 + 3 =
x^2 + 4x + 2

Answer 6

do i alwas have to write x first meaning it would be wrong if i wrote it as 4x + x^2 + 2?

Answer 7

always

Answer 8

No, either way it's correct, but it's conventional to write the terms in descending order of the powers of x.

Answer 9

ok. thanks so much 4 ur help :)

Answer 10

You're welcome.