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anonymous
 one year ago
Hi I'm new to open study, If someone could please help me with these 3 questions. I cant seem to get them right.
1) Given the following functions f(x) and g(x), solve for (f ⋅ g)(2) :
f(x) = 3x2 + 2
g(x) = x − 8
2) Given the following functions f(x) and g(x), solve f[g(10)]
f(x) = 10x + 8
g(x) = x + 9
3) Given the following functions f(x) and g(x), solve (f + g)(3)
f(x) = 2x + 21
g(x) = x − 24
anonymous
 one year ago
Hi I'm new to open study, If someone could please help me with these 3 questions. I cant seem to get them right. 1) Given the following functions f(x) and g(x), solve for (f ⋅ g)(2) : f(x) = 3x2 + 2 g(x) = x − 8 2) Given the following functions f(x) and g(x), solve f[g(10)] f(x) = 10x + 8 g(x) = x + 9 3) Given the following functions f(x) and g(x), solve (f + g)(3) f(x) = 2x + 21 g(x) = x − 24

This Question is Closed

phi
 one year ago
Best ResponseYou've already chosen the best response.1(f ⋅ g)(2) is short for f(2) * g(2) can you find f(2) ?

anonymous
 one year ago
Best ResponseYou've already chosen the best response.0I have no idea how to start.

phi
 one year ago
Best ResponseYou've already chosen the best response.1they give you a formula f(x) = 3x^2 + 2 f(x) is the "short name" and 3x^2 + 2 is the formula f(2) means: find the formula, find the "x" in the formula and replace the x with a 2 can you do that?

phi
 one year ago
Best ResponseYou've already chosen the best response.1no. how did you get that? remember order of operations first do exponents, so first do 2^2

anonymous
 one year ago
Best ResponseYou've already chosen the best response.0Well I replaced the x with 2. And the formula is 3x^2 + 2. Is it 16?

anonymous
 one year ago
Best ResponseYou've already chosen the best response.03 times 4 is 12 and 12 plus 2 is 14. Sorry 14?

phi
 one year ago
Best ResponseYou've already chosen the best response.1it is worth knowing how to do this. 3*2^2 +2 first do 2^2 which is 2*2 . you get 4 so you have 3*4 +2 12+2 14 yes 14

phi
 one year ago
Best ResponseYou've already chosen the best response.1(f ⋅ g)(2) is short for f(2) * g(2) so far we have f(2) is 14 now we need g(2) can you do that ?

phi
 one year ago
Best ResponseYou've already chosen the best response.1to find g(2) find the formula for g replace any x's in the formula with 2 simplify

anonymous
 one year ago
Best ResponseYou've already chosen the best response.0How do I find the formula for g?

anonymous
 one year ago
Best ResponseYou've already chosen the best response.0Oh they gave me the formula

phi
 one year ago
Best ResponseYou've already chosen the best response.1they give it to you. g(x) is the "name" they give to x8 that is what g(x) = x − 8 means

phi
 one year ago
Best ResponseYou've already chosen the best response.1yes, and that simplifies to what?

phi
 one year ago
Best ResponseYou've already chosen the best response.1ok now we have (f ⋅ g)(2) is short for f(2) * g(2) so far we have f(2) is 14 and g(2) is 6 now we multiply to get the final answer

anonymous
 one year ago
Best ResponseYou've already chosen the best response.0Thankyou! Can you help with the other 2?

phi
 one year ago
Best ResponseYou've already chosen the best response.1Let's skip to Q3 (f + g)(3) f(x) = 2x + 21 g(x) = x − 24 can you guess what (f+g)(3) is short for ? (based on the first question)

phi
 one year ago
Best ResponseYou've already chosen the best response.1it would be better to say f(3) + g(3)

anonymous
 one year ago
Best ResponseYou've already chosen the best response.0f(3)=2(3)+21 f(3)=27?

anonymous
 one year ago
Best ResponseYou've already chosen the best response.0So g(x) = x − 24 g(3)=324 g(3)= 21?

phi
 one year ago
Best ResponseYou've already chosen the best response.1ok, but we are doing (f + g)(3) = f(3) + g(3)

anonymous
 one year ago
Best ResponseYou've already chosen the best response.0Ok so what do we do know that we know what f and g are?

phi
 one year ago
Best ResponseYou've already chosen the best response.1yes. notice in Q1 we have multiply (that is what the dot means) and in this question we are adding we might also see (fg)(3) (subtract) or (f/g)(3) divide

phi
 one year ago
Best ResponseYou've already chosen the best response.1now Q2 this one is a bit different. The formulas are not combined using add or multiply we have something called "composition" (they have to call it something)

anonymous
 one year ago
Best ResponseYou've already chosen the best response.0My answer choices are: 98 198 190 2052

phi
 one year ago
Best ResponseYou've already chosen the best response.1those are the choices for (f + g)(3) where f(x) = 2x + 21 g(x) = x − 24 ??

phi
 one year ago
Best ResponseYou've already chosen the best response.1those look like the choices for Q2 which we have not done yet

anonymous
 one year ago
Best ResponseYou've already chosen the best response.0Oh Im sorry I got confused

anonymous
 one year ago
Best ResponseYou've already chosen the best response.0The answer was 6 sorry

phi
 one year ago
Best ResponseYou've already chosen the best response.1Q2 solve f[g(10)] f(x) = 10x + 8 g(x) = x + 9 think of g(10) as some number (which it is) let's find g(10) can you do that ?

phi
 one year ago
Best ResponseYou've already chosen the best response.1yes, and that simplifies to 19 so g(10) is 19 if we replace g(10) with 19 in f[g(10)] we get f(19) (the [ vs ( is just to make it easier to read in f[g(10)] ... but it means the same as parens) anyway we have figured out that f[g(10)] is the same as f(19) now we need to find f(19)

anonymous
 one year ago
Best ResponseYou've already chosen the best response.0f(x) = 10x + 8 So f(19)=10(19)+8?

phi
 one year ago
Best ResponseYou've already chosen the best response.1ok, and what number do you get?

phi
 one year ago
Best ResponseYou've already chosen the best response.1you do 10 times 19 then add 8

anonymous
 one year ago
Best ResponseYou've already chosen the best response.0Thankyou so so much. I got a 100%! I havent gotten a 100% before. You're a really good tutor!
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