中二數學公式(主項變換)

1.(a-b)x-(a+b)y=0 [a]
ax - bx - ay - by = 0
a(x - y) - b(x + y) = 0
a(x - y) = b(x + y)
a = b(x + y) / (x - y)
2.1/y=1/x+c [x]
1 / y - c = 1 / x
(1 - cy) / y = 1 / x
x = y / (1 - cy)
3.q=p/a+p/b [p]
q = p (1 / a + 1 / b)
q = p (a + b) / ab
p = qab / (a + b)
希望解答到你 ^^

2007-11-22 22:42:32 補充：
其實最簡單既方法就係expand開它...之後再將相同既野放一齊...最後再移項解決

3.q=p/a+p/a
q=p(1/a+1/b)
q=p(b+a)/ab
qab/(b+a)=p
p=qab/(b+a)