Most annoying maths questions

Here how I did and never get it correct...

h(x) = 3x - 2
h(x + 1)

x + 1 = 3x - 2
(-1) (-1)

x = 3x - 3 it says 3x - 1 is the answer...

--------------------------------------------------------------------------

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

3x = x^2 +5x -1
the answer was 9x^2 + 15x - 1 and I can't get my head around this one at all.


Does anyone understand these questions and help me out? Thanks.

Hi there, could you write out exactly what the question is?

Can you post a picture of the question? Thanks.

First question.
h(x) = 3x - 2

Work out expressions, giving answers in the simplest form.
ii) h(x+1)

Second question.
f(x) = x^2 + 5x - 1

Work out expressions, giving answers in simplest form.
i) f(3x)

Topic* is function notation.

First question.
h(x) = 3x - 2

Work out expressions, giving answers in the simplest form.
ii) h(x+1)

Second question.
f(x) = x^2 + 5x - 1

Work out expressions, giving answers in simplest form.
i) f(3x)

Topic* is function notation.

Like a number machine, "f(x)" and "h(x)" are functions with an input of whatever is in the bracket.

So if h(x) = 3x - 2, it means take whatever x is, multiply by three, and subtract two.

If the input is "x+1", however, it means add one to x first, then multiply by three, then subtract two.

So h(x+1) = 3(x+1) -2
= 3x +3 -2
= 3x +1