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Anyone know how to do functions 😖

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I really don’t understand them please help
Original post by Fayeeeee

I really don’t understand them please help


What don't you get??

f(x)=3x−2f(x) = 3x-2, so when we say f(number)f(\text{number}) we look at 3x−23x-2 and replace xx by (number)(\text{number}) before simplifying everything.

So f(2)=3(2)−2=6−2=4f(2) = 3(2)-2 = 6-2 = 4.

Same idea for pretty much the first half of these questions.
Reply 2
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Fayeeeee
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Original post by RDKGames
What don't you get??

f(x)=3x−2f(x) = 3x-2, so when we say f(number)f(\text{number}) we look at 3x−23x-2 and replace xx by (number)(\text{number}) before simplifying everything.

So f(2)=3(2)−2=6−2=4f(2) = 3(2)-2 = 6-2 = 4.

Same idea for pretty much the first half of these questions.

Original post by RDKGames
What don't you get??

f(x)=3x−2f(x) = 3x-2, so when we say f(number)f(\text{number}) we look at 3x−23x-2 and replace xx by (number)(\text{number}) before simplifying everything.

So f(2)=3(2)−2=6−2=4f(2) = 3(2)-2 = 6-2 = 4.

Same idea for pretty much the first half of these questions.


Ahh thanks, my teachers not the best😂
I don’t understand the ones past 5 thou
(edited 5 years ago)
Original post by Fayeeeee
Ahh thanks, my teachers not the best😂
How do you do the ones for number 2 thou ?


Same thing!

f(3)+g(−2)f(3) + g(-2) means you work out f(3)f(3) first of all, then g(−2)g(-2).

Then add them.
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Fayeeeee
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Original post by RDKGames
Same thing!

f(3)+g(−2)f(3) + g(-2) means you work out f(3)f(3) first of all, then g(−2)g(-2).

Then add them.


Ahh, I realised after I wrote it ahah
I don’t understand any past 5 thou, how do you apply it?
Original post by Fayeeeee
Ahh, I realised after I wrote it ahah
I don’t understand any past 5 thou, how do you apply it?


What do you mean? The questions 5, 6, 7 define new functions but the process is the same.
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Fayeeeee
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Original post by RDKGames
What do you mean? The questions 5, 6, 7 define new functions but the process is the same.


Ohh right thankss
Last question 😂, for 8/9/10 are you working backwards I don’t really know
Original post by Fayeeeee
Ohh right thankss
Last question 😂, for 8/9/10 are you working backwards I don’t really know


Working backwards?? Not sure what you mean.

A function ff is defined as 2x+22x+2, and then as 88. Since these represent the same function, they must be equal: 2x+2=82x+2=8. This allows you to solve for xx.

Same process for all three.
yep, for 8 it is 2x+2=8 and rearrange
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Fayeeeee
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Original post by RDKGames
Working backwards?? Not sure what you mean.

A function ff is defined as 2x+22x+2, and then as 88. Since these represent the same function, they must be equal: 2x+2=82x+2=8. This allows you to solve for xx.

Same process for all three.


Ahhhh, thank you so much you’ve really helped me and I appreciate it allot! 🙂
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Fayeeeee
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Original post by ThunderBeard
yep, for 8 it is 2x+2=8 and rearrange


😊 thank you

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