JAMB - Mathematics (2008 - No. 16)
If p varies inversely as the square of q and p = 8 when q = 4, find q when p = 8
\(\pm\)16
\(\pm\)8
\(\pm\)4
\(\pm\)2
Spiegazione
p ∝ \(\frac{1}{q}\)
p = \(\frac{k}{q}\)
K = q\(^2\)p
= 4\(^2\)(8)
∴p = 128/q
32 = 128/q
q\(^2\) = 128/32
q\(^2\) = 4
q = √4 = \(\pm\) 2
p = \(\frac{k}{q}\)
K = q\(^2\)p
= 4\(^2\)(8)
∴p = 128/q
32 = 128/q
q\(^2\) = 128/32
q\(^2\) = 4
q = √4 = \(\pm\) 2