1.6: Linear law: gradient of $\lg y$ against $x^{2}$

0606/11/O/N/17 — Question 4 · 6 marks

When

\lg y

is plotted against

x^{2}

a straight line is obtained which passes through the points

(4, 3)

and

(12, 7)

(i)

Find the gradient of the line.

[1]

(ii)

Use your answer to part (i) to express

\lg y

in terms of

x

[2]

(iii)

Hence express

y

in terms of

x

, giving your answer in the form

y = A(10^{bx^{2}})

where

A

and

b

are constants.

[3]

1.6: Linear law: gradient of lg⁡y\lg ylgy against x2x^{2}x2