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2 votes
F(x)=3x-8

--------
6x

Find and simplify

f(3)-f(1)
------------
3-1

I have no idea what this question is, any ideas?

User Anup Ash
by
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1 Answer

4 votes
What this is asking is for you to plug values into the following function:
f(x)=(3x-8)/(6x)

Since the question is asking you to find
f(3)-f(1), this is how you work it out:
You take the function;

f(x)=(3x-8)/(6x)
And plug the numbers indicated in for x;

f(x)=(3x-8)/(6x)\\ f(3)=(3(3)-8)/(6(3))\\ f(3)=(9-8)/(18)\\ f(3)=(1)/(18)\\\\ f(1)=(3(1)-8)/(6(1))\\ f(1)=(3-8)/(6)\\ f(1)=(-5)/(6)\\\\ Now\ what\ you\ do\ is\ you\ subract\ f(3)\ and\ f(1).\\ f(3)-f(1)\\ f(3)-f(1)=(1)/(18)-(-5)/(6)\\ f(3)-f(1)=(1)/(18)-(-15)/(18)\\ f(3)-f(1)=(1+15)/(18)\\ f(3)-f(1)=(16)/(18)=(8)/(9)
So the answer to f(3) - f(1) =
(8)/(9)
User Amin SCO
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8.2k points