I need math help! Please and thanks

[Naurthon]

12)

For this one you need to multiply the numerator and the denominator both by 3 SQRT(X) + SQRT(Y). Note that this is the denominator, but you have changed the sign of the last term (made it positive instead of negative). Multiplying both the numerator and denominator by this term is the same as multiplying it by one, so nothing has really changed. Now just do the multiplication of the terms and you'll come out with Answer C.

[Naurthon]

For the second sets of sample questions, I'm going to have to bail on the trig. I had one trig class something like 20 years ago and very little call to use it since then. It is pretty much all gone.

[Naurthon]

3) g(f(3))

At first this looks at first like you're supposed to figure out what the formulas for f() and g() are. Don't bother. The answers are in the table. For this sort of thing, just start on the inside and work out. Look up f(3) on the table given. f(3)=2. Now look up g(2) on the other table. g(2)=-3. g(f(3))=-3. Answer B.

[Naurthon]

4) equivalent expression.

What you need to know for this is that roots and be expressed as inverse exponents. For example, the square root of 4 can be written as 4^1/2 (four to the one-half power). The cube root of 8 is 8^1/3 (eight to the one-third power). The fourth root of 7 squared can be written as 7^2/4. Further, it can be simplified as 7^1/2.

Apply this idea and you'll see that Answer D is correct.

[Bri]

Thanks a lot!!