1.20: Linear law: lgy\lg y against x2x^{2}

0606/13/O/N/20 — Question 6 · 8 marks

It is known that y=A×10bx2y = A \times 10^{bx^{2}}, where AA and bb are constants. When lgy\lg y is plotted against x2x^{2}, a straight line passing through the points (3.63,5.25)(3.63, 5.25) and (4.83,6.88)(4.83, 6.88) is obtained.
(a)
Find the value of AA and of bb.
[4]
(b)
Find the value of yy when x=2x = 2.
[2]
(c)
Find the positive value of xx when y=4y = 4.
[2]