Question

what is f(x) ?
if f(x-1)=x^2+3x+5

Answer 1

I'm not sure, but I think its (x + 1)^2 + 3(x - 1) + 5

Answer 2

f(x) = f[(x -1) + 1]

Answer 3

yup that's right @pratu043 :)

Answer 4

explain @pratu043

Answer 5

lol look at what i wrote...f(x-1 + 1) = f(x + 0) = f(x)

since f(x-1) = x^2 + 3x + 5

f(x - 1 + 1) = (x+1)^2 + 3(x+1) + 5

got the logic?

Answer 6

1 and 1 will be cancelled then there will f(x) I didn't get.

Answer 7

hmmm you get that f(x-1 + 1) = f(x) right?

Answer 8

now let a = x-1

f(a) = a^2 + 3a + 5

agree?

Answer 9

yes...

Answer 10

now like i said f(x) = f(x-1 + 1) = f(a+1)

therefore

f(a + 1) = (a+ 1)^2 + 3(a+1) + 5

Answer 11

oops i made a mistake o.O

Answer 12

substituting a made me confused -_-

Answer 13

which mistake.......

Answer 14

I am also confused ...........

Answer 15

substituting will actually make it complicated..let me start again

do you get that f[(x-1) + 1] = f(x)?

Answer 16

yes now I am clear thank you...........

Answer 17

really? lol..great