1.45: Quadratic graphs

4PM1/1/June/2015 — Question 3 · 5 marks

f(x)=4x^2-8x+7

Given that

f(x)=l(x-m)^2+n

, for all values of

x

,

(a) find the value of

l

, the value of

m

and the value of

n

. (3)

(b) Hence, or otherwise, find

(i) the minimum value of

f(x)

,

(ii) the value of

x

for which this minimum occurs. (2)