SOLUTION: f(x)=x^2-3 h(x)=3Ix-9I-10 I= absolute value sign Find f(h(4))

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Question 1189756: f(x)=x^2-3
h(x)=3Ix-9I-10 I= absolute value sign
Find f(h(4))

Found 2 solutions by MathLover1, ikleyn:
Answer by MathLover1(20850) About Me  (Show Source):
You can put this solution on YOUR website!

f%28x%29=x%5E2-3
h%28x%29=3abs%28x-9%29-10+
Find f%28h%284%29%29

f%28h%28x%29%29=f%283abs%28x-9%29-10+%29

f%28h%28x%29%29=%283abs%28x-9%29-10+%29%5E2-3

plug in x=4

f%28h%284%29%29=%283abs%284-9%29-10+%29%5E2-3

f%28h%284%29%29=22

Answer by ikleyn(52790) About Me  (Show Source):
You can put this solution on YOUR website!
.
f(x)=x^2-3
h(x)=3Ix-9I-10 I= absolute value sign
Find f(h(4))
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           A simplest and the most natural way to complete such assignment
           is to do things / calculations step by step,

           WITHOUT  COMBINING  THEM  INTO  ONE  FORMULA.


Step 1.  First, calculate h(4) = 3 * |4 - 9| - 10 = 3*5 - 10 = 15-10 = 5.


Step 2.  Now calculate f(h(4)) simply substituting the found value 5 
         instead of h(4) into the formula for f

             f(h(4)) = f(5) = 5^2 - 3 = 25 - 3 = 22.    ANSWER

Done and completed.   //   Done and completed.   //   Done and completed.

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Making other way,  as @MathLover1 does,  is  REALLY  BAD  WAY.

She instructs you to derive complicated formula and then follow this complicated formula, while there is much more simple way.


Following the  @MathLover1 methodology,  you  INEVITABLY  will make many mistakes on the way,

while making it step by step,  as I instruct you,  SIMPLIFIES  you work and make it much more error-proof.


Again,  in this assignment,  NOBODY  REQUIRES  you to derive long formula for the composition.

It is  UNNECESSARY  EXCESSIVE  job,  which will lead you to making mistakes.


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From appearing the post by @MathLover1,  there was only one benefit for you.

This benefit was that I came and explained you how to do it in a right way and warned you do not follow her way . . .