✔ 最佳答案
解答條題主項變換,詳細列明步驟
你應該要講清楚想變換做邊個主項喎！不過我而家逐個同你做曬佢，你自己再揀下應該用邊個啦。
1.
2a(y-x)=3b(x+y)
【變換做a】
2a(y-x)=3b(x+y)
a = [3b(x + y)]/[2(y - x)]
【變換做b】
2a(y-x)=3b(x+y)
b = [2a(y - x)]/[3(x + y)]
【變換做x】
2a(y-x)=3b(x+y)
2ay - 2ax = 3bx + 3by
2ay - 3by = 3bx + 2ax
(2a - 3b)y = (3b + 2a)x
x = (2a - 3b)y/(3b + 2a)
【變換做y】
2a(y-x)=3b(x+y)
2ay - 2ax = 3bx + 3by
2ay - 3by = 3bx + 2ax
(2a - 3b)y = (3b + 2a)x
y = (3b + 2a)x/(2a - 3b)
2.
1/x+1/y=1/m
【變換做x】
1/x + 1/y = 1/m
1/x = 1/m - 1/y
1/x = (y - m)/(my)
x = my/(y - m)
【變換做y】
1/x + 1/y = 1/m
1/y = 1/m - 1/x
1/y = (x - m)/(mx)
y = (mx)/(x - m)
【變換做m】
1/x + 1/y = 1/m
(y + x)/(xy) = 1/m
m = xy/(y + x)
3.
(3 - a)/(b - c) = (a - 2)/(c + 1)
【變換做a】
(3 - a)(c + 1) = (a - 2)(b - c)【交叉相乘】
3c + 3 - ac - a = ab - ac -2b + 2c
3c + 3 + 2b - 2c = ab - ac + ac - a
c + 2b + 3 = ab - a
c + 2b + 3 = a(b - 1)
a = (c + 2b + 3)/(b - 1)
【變換做b】
(3 - a)(c + 1) = (a - 2)(b - c)【交叉相乘】
3c + 3 - ac - a = ab - ac -2b + 2c
3c + 3 - ac - a + ac - 2c = ab - 2b
c - a + 3 = b(a - 2)
b = (c - a + 3)/(a - 2)
【變換做c】
(3 - a)(c + 1) = (a - 2)(b - c)【交叉相乘】
3c + 3 - ac - a = ab - ac -2b + 2c
3c - ac + ac - 2c = ab - 2b - 3 + a
c = (a - 2)b + a - 3
4.
vt = (v + 3) + (t - 4)
【變換做v】
vt = (v + 3) + (t - 4)
vt = v + t - 1
vt - v = t - 1
v(t - 1) = t - 1
v = (t - 1)/(t - 1) = 1
【變換做t】
vt = (v + 3) + (t - 4)
vt = v + t - 1
vt - t = v - 1
t(v - 1) = v - 1
t = (v - 1)/(v - 1) = 1
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解答條題化簡,詳細列明步驟
1.
(x - 3)/(x + 3) + (x + 3)/(x - 3)
= (x - 3)(x - 3)/[(x + 3)(x - 3)] + (x + 3)(x + 3)/[(x - 3)(x + 3)]【通分母】
= [(x² - 3x - 3x + 9) + (x² + 3x + 3x + 9)]/[(x - 3)(x + 3)]
= [(x² - 6x + 9) + (x² + 6x + 9)]/[(x - 3)(x + 3)]
= (2x² + 18)/[(x - 3)(x + 3)]
= 2(x² + 9)/[(x - 3)(x + 3)]
2.
(x + 3)/(x - 2) + (x + 2)/(x - 3)
= (x + 3)(x - 3)/[(x - 2)(x - 3)] + (x + 2)(x - 2)/[(x - 3)(x - 2)]【通分母】
= [(x² - 3x + 3x - 9) + (x² - 2x + 2x - 4)]/[(x - 2)(x - 3)]
= [(x² - 9) + (x² - 4)]/[(x - 2)(x - 3)]
= (2x² - 13)/[(x - 2)(x - 3)]
希望幫倒你！^^【不過下次記住寫番清楚條題目啦！】
