Question

How would I solve this? f(x)=x^2+3 at f(2x+1)

Answer 1

I know I would separate 2x+1^2

Answer 2

replace "x" with "2x+1" in x^2+3

Answer 3

be very careful with parentheses

Answer 4

Yeah did that so I got (2x+1)^1+3

Answer 5

the exponent is 2, not 1

(2x+1)^2+3

then you'd use FOIL to expand (2x+1)^2

Answer 6

(2x+1)(2x+1)

Answer 7

yup, keep going

first, outer, inner, last

Answer 8

4x+(2x+1)(1+2x)+2

Answer 9

you're supposed to multiply along the arrows, not add

Answer 10

(2x+1)(2x+1)

first terms: 2x and 2x

2x * 2x = 4x^2

and keep going with the outer/inner/last terms

Answer 11

4x^2+2x+2x+1

Answer 12

good, you can combine 2x and 2x to get 4x

so 4x^2+4x+1

you still have the +3 from the original function

so 4x^2+4x+4 = your sol'n

Answer 13

so i would add the 3 just to the 1?

Answer 14

yes
you started with
(2x+1)^2+3

after expanding you end up with

2x^2 + 4x + 1 + 3

the 1 and 3 combine to get 4