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anonymous
 one year ago
Let f(x) = 2x  7 and g(x) = 4x + 3. Find (f o g)(5)
anonymous
 one year ago
Let f(x) = 2x  7 and g(x) = 4x + 3. Find (f o g)(5)

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jim_thompson5910
 one year ago
Best ResponseYou've already chosen the best response.3(f o g)(5) is the same as f(g(5)) the first task is to find g(5). Do you know how to do this?

anonymous
 one year ago
Best ResponseYou've already chosen the best response.0Could you help @jim_thompson5910

jim_thompson5910
 one year ago
Best ResponseYou've already chosen the best response.3g(x) = 4x + 3 g(5) = 4(5) + 3 ... replace every x with 5 g(5) = ??

misssunshinexxoxo
 one year ago
Best ResponseYou've already chosen the best response.0On OS we help people learn; Jim is trying to make sure you are understanding this

anonymous
 one year ago
Best ResponseYou've already chosen the best response.0Oh i know and i defiantly want the help

UsukiDoll
 one year ago
Best ResponseYou've already chosen the best response.1(f o g)(5) well first let's do (f o g ) which means that the g(x) equation is placed inside the f(x) equation

UsukiDoll
 one year ago
Best ResponseYou've already chosen the best response.1whoa... let's do this step by step

anonymous
 one year ago
Best ResponseYou've already chosen the best response.0Oh sorry i was replying to what @jim_thompson5910 started

jim_thompson5910
 one year ago
Best ResponseYou've already chosen the best response.3so you should find that g(5) = 23 agreed?

jim_thompson5910
 one year ago
Best ResponseYou've already chosen the best response.3f(g(5)) becomes f(23) after you replace g(5) with 23

jim_thompson5910
 one year ago
Best ResponseYou've already chosen the best response.3now follow the same basic steps to calculate f(23)

UsukiDoll
 one year ago
Best ResponseYou've already chosen the best response.1ok it's ok didn't see that :) anyway given the functions f(x) = 2x7 and g(x) = 4x+3 we need to place g(x) =4x+3 into the f(x) so for every x in f(x) the g(x) takes it's place

UsukiDoll
 one year ago
Best ResponseYou've already chosen the best response.1so the end result should be 2(insert g(x) function here)7

UsukiDoll
 one year ago
Best ResponseYou've already chosen the best response.1then combine like terms and evaluate when x = 5

UsukiDoll
 one year ago
Best ResponseYou've already chosen the best response.1I agree with jim there's more to be done...

anonymous
 one year ago
Best ResponseYou've already chosen the best response.0ok im ready to learn the rest

UsukiDoll
 one year ago
Best ResponseYou've already chosen the best response.1k.. so did you already place your g(x) into your entire f(x) function?

anonymous
 one year ago
Best ResponseYou've already chosen the best response.0No i got lost after we got f(23)

jim_thompson5910
 one year ago
Best ResponseYou've already chosen the best response.3To calculate f(23), replace every x in f(x) with 23 f(x) = 2x  7 f(23) = 2*23  7 f(23) = ??

UsukiDoll
 one year ago
Best ResponseYou've already chosen the best response.1that means x = 23 evaluate the f(x) function

jim_thompson5910
 one year ago
Best ResponseYou've already chosen the best response.3it's just like the g(x) one

UsukiDoll
 one year ago
Best ResponseYou've already chosen the best response.1we have two negative numbers so the negative numbers are supposed to increase, not decrease

UsukiDoll
 one year ago
Best ResponseYou've already chosen the best response.1do you want to see another method of solving this equation as a reference?

anonymous
 one year ago
Best ResponseYou've already chosen the best response.0yes that would be great

UsukiDoll
 one year ago
Best ResponseYou've already chosen the best response.1ok so here's how I would tackle this problem (f o g ) (5) first I will tackle f o g portion and then evaluate when x = 5 so f o g means that we place our g(x) function inside all x's of the f(x) function f(x) = 2x7 and g(x) = 4x+3 f o g 2(4x+3)7 distribute the 2 8x67 8x13 so our f o g = 8x13 now evaluating when x = 5 f o g (5) = 8(5)13 = 4013 = 53

anonymous
 one year ago
Best ResponseYou've already chosen the best response.0Can you guys help me solve another @UsukiDoll @jim_thompson5910

anonymous
 one year ago
Best ResponseYou've already chosen the best response.0Let f(x) = x + 2 and g(x) = x2 Find ( g o f)(5)

UsukiDoll
 one year ago
Best ResponseYou've already chosen the best response.1\[\large f(x) = x+2, g(x) = x^2 \]

UsukiDoll
 one year ago
Best ResponseYou've already chosen the best response.1this is similar to the previous problem. while our x still remains the same g o f means that we place our entire f(x) function inside the x's of the g(x) function so g o f = (insert f(x) here)^2

UsukiDoll
 one year ago
Best ResponseYou've already chosen the best response.1our f(x) = x+2 and we need place it inside g(x). Since g(x) =x^2 g o f = (f(x) function)^2

UsukiDoll
 one year ago
Best ResponseYou've already chosen the best response.1\[g o f =(x+2)^2 \] that second power means write (x+2) two times after that, we need to use FOIL to expand

anonymous
 one year ago
Best ResponseYou've already chosen the best response.0your gonna have to hold my hand on this one cuz im totally lost lol im sorry

UsukiDoll
 one year ago
Best ResponseYou've already chosen the best response.1alirght.. so we write (x+2) two times (x+2)^2 means (x+2)(x+2) now using FOIL (x)(x)+2(x)+2(x)+(2)(2) so what's 2 x 2 2x + 2x and x times x I guess that's the closest way of notating multiplication

anonymous
 one year ago
Best ResponseYou've already chosen the best response.0Ok so where do we go from this?

UsukiDoll
 one year ago
Best ResponseYou've already chosen the best response.1first tell me what 2 x 2 is then tell me what 2x+2x is .. I will factor out the x to make it easier x(2+2)

UsukiDoll
 one year ago
Best ResponseYou've already chosen the best response.1mhm last one what is (x)(x) . I'll make this easier by rewriting it and using the addition exponential rule, \[\large (x)(x) \rightarrow x^1x^1 \rightarrow x^{1+1}\] so you just have to solve for the exponent part. what is 1+ 1

UsukiDoll
 one year ago
Best ResponseYou've already chosen the best response.1yes so now we have \[g o f =x^2+4x+4 \]

UsukiDoll
 one year ago
Best ResponseYou've already chosen the best response.1so now we evaluate this when x = 5. so replace all x's with 5

UsukiDoll
 one year ago
Best ResponseYou've already chosen the best response.1\[g o f (5) =(5)^2+4(5)+4\] \[g o f (5) =2520+4 \rightarrow 5+4 = 9 \] correct
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