Skip to content
MathsGenie logo
Quick links
Open app

Course home

  1. A Level
  2. Maths WJEC
  3. Question bank

3.2.3 Algebra and Functions (A-level only)

EasyMediumHard
1234567891011121314151617181920212223242526272829303132333435363738394041424344454647484950515253545556575859
Question 48

The cooling efficiency, EEE, of a high-performance server rack is modelled by the function

E(v)=5v−2v−4,v>4 E(v) = \frac{5v - 2}{v - 4}, \quad v > 4 E(v)=v−45v−2​,v>4

where v v\,v is the coolant flow rate in litres per minute.

a.

Use differentiation to show that E E\,E is a decreasing function on its domain.

[3]
b.

Find an expression for E−1(v)E^{-1}(v)E−1(v) and state its domain.

[4]
ci.

Show that the composite function EE(v)EE(v)EE(v) can be written in the form av+bv+c\displaystyle \frac{av + b}{v + c}v+cav+b​, where a,b, a, b,\,a,b, and c c\,c are integers to be found.

[3]
cii.

Deduce the range of EEEEEE.

[3]

3.2.3 Algebra and Functions (A-level only) Questions

  1. A Level
  2. /Maths
  3. /3.2.3 Algebra and Functions (A-level only)