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# P2 - Pure maths watch

1. Given that P^2 + Q^2 = 14pq

Proove that lg(p+q) - lg4 = 1/2(lgp + lgq)
2. Stop posting your homework, on here, expecting all of us to do it!
try for yourself, for once
3. I'd help but I'm stumped on this one.
4. Ive been posting since a month back now, and its not homework. Its exam revision questions I am stuck on. The P2 exam is this monday, I somehow doubt it is homework? Also if you don't want to help, don't
Given that p^2 + q^2 = 14pq
Prove that lg(p+q) - lg4 = 1/2(lgp + lgq)
p^2 + q^2 = 14pq
-> (p + q)^2 - 2pq = 14pq
-> (p + q)^2 = 16pq
-> lg[(p + q)^2] = lg(16pq)
-> 2lg(p + q) = lg(16pq)
-> 2lg(p + q) = lg(16) + lg(pq)
-> lg(p + q) = (1/2)lg(16) + (1/2)lg(pq)
-> lg(p + q) = lg(4) + (1/2)lg(pq)
-> lg(p + q) - lg(4) = (1/2)[lg(p) + lg(q)]
6. i managed to do this!!

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