Khan/khan-exercises — Issue #14390: Functions 3 - i think -1^2 = 1
Author: KhanBugz
Created: 2012-02-22 06:06:54+00:00
State: open
Labels: ie8, wrong-or-unclear, xp

Reporter: andyJlester@gmail.com

First, let's solve for the value of the inner function, h(1) h(1). Then we'll know what to plug into the outer function.

h(1)=(2)(1)−3(g(1)) h(1) = (2)(1)-3(g(1))

To solve for the value of h h,we need to solve for the value of g(1) g(1).

g(1)=−1 2 +(−2)(1)−3(f(1)) g(1) = -1^{2}+(-2)(1)-3(f(1))

To solve for the value of g g,we need to solve for the value of f(1) f(1).

f(1)=(3)(1)−3 f(1) = (3)(1)-3

f(1)=0 f(1) = 0

That means g(1)=−1 2 +(−2)(1)+(−3)(0) g(1) = -1^{2}+(-2)(1)+(-3)(0)

g(1)=−3

i make this
1+(-2)+0 = -1 not -3

where am i going wrong?
(i am using you work to teach Thai kids math by the way, thanks for you producing all this, if i can help in any way feel free to ask me)

[functions_3.html?seed=107&problem=1](http://sandcastle.khanacademy.org/media/castles/Khan:master/exercises/functions_3.html?seed=107&problem=1&debug)

[Answer timeline](http://sandcastle.khanacademy.org/media/castles/Khan:master/exercises/functions_3.html?seed=107&problem=1&debug&activity=%5B%5B%22incorrect-activity%22%2C%22%5C%225%5C%22%22%2C263%5D%2C%5B%22hint-activity%22%2C%220%22%2C5%5D%2C%5B%22hint-activity%22%2C%220%22%2C18%5D%2C%5B%22hint-activity%22%2C%220%22%2C20%5D%2C%5B%22hint-activity%22%2C%220%22%2C20%5D%2C%5B%22hint-activity%22%2C%220%22%2C40%5D%2C%5B%22hint-activity%22%2C%220%22%2C41%5D%2C%5B%22hint-activity%22%2C%220%22%2C41%5D%2C%5B%22hint-activity%22%2C%220%22%2C42%5D%2C%5B%22hint-activity%22%2C%220%22%2C42%5D%2C%5B%22hint-activity%22%2C%220%22%2C42%5D%2C%5B%22hint-activity%22%2C%220%22%2C43%5D%2C%5B%22hint-activity%22%2C%220%22%2C43%5D%2C%5B%22hint-activity%22%2C%220%22%2C44%5D%5D)

["5"]

Mozilla/4.0 (compatible; MSIE 8.0; Windows NT 5.1; Trident/4.0; GTB7.2; AskTbPTV/5.12.2.16749; .NET CLR 2.0.50727)

MathJax is loaded, ready, queue length: 0