# P1 Maths October November 2005 question 8

#### XWTBSILT

Can someone answer only part 2 of (ii)

A function f is defined by f : x ? (2x ? 3)3 ? 8, for 2 ? x ? 4.

(i) Find an expression, in terms of x, for f(x) and show that f is an increasing function. [4]
(ii) Find an expression, in terms of x, for f?1(x) and find the domain of f?1. [4]

this is the inverse function of f(x)

(cuberoot of x+8/2) + 1.5
Can someone find the domian,please include all ur steps and can u find the range of f(x) what i mean is like is there a way to find it...so that then finding the domain of f inverse is easy

#### khizarr

the range of f inverse(x) is the domain of f(x) and vice versa .
substitute 2 and 4 in the original equation and u'll get the range.
for the inverse, take y= equation, make y the subject and equate it to x . try it ..

#### SZ11

What do the '?' mean? Cause there are a lot of them and they don't make sense to me...

#### khizarr

i think so that its for the sign of inverse, greater than, less than, - , + , =