Question

f(x)=ax+b given that f(2)=1 and f(5)=7

solve equation of ff(X)

Answer 1

f(2)=1, and f(5)=7, so we can build two equations with unknowns a and b

Answer 2

1 = a2+b
7 = a5+b

Answer 3

or if i write it properly:
2a+b=1
5a+b=7

Answer 4

alright i have a =2.5 and b=-4

Answer 5

b = 1-2a
5a+1-2a=7
3a = 6
a=2

Answer 6

b = 1-4=-3

Answer 7

ok

Answer 8

now lets solve

Answer 9

that is, we've solved it.
f(x) = 2x-3

Answer 10

no its ff(x)

Answer 11

we should solve for f^2

Answer 12

which means we are going to substitute our values using the values of a and b on the equation

Answer 13

ohhh then just multiply it by itself.. i think

Answer 14

Um getting a different answer i just don know y the correct answer is 2.25

Answer 15

i honestly dont even understand the question

Answer 16

Oh soorry it says the equation ffx=0

Answer 17

what's ff(x)?

Answer 18

ohh wait

Answer 19

f(f(X)) = 2(2x-3)-3 = 0
4x - 6 - 3 = 0
4x = 9
x = 9/4

Answer 20

I was reading from one textbook it means f^2

Answer 21

No it doesn't mean f^2.. well not really

Answer 22

wow explain

Answer 23

f(x) = 2x-3, right?
or
f(a) = 2a-3
or
f(random) = 2 random - 3?

Answer 24

yeah ryt

Answer 25

do u understand what I'm doing there?
\[f(\Delta)=2\Delta-3\]

Answer 26

So now you have:
f(f(x)), but f(x) = 2x-3, so replace the x in the f(x) with 2x-3