√125×√50÷√1000 （答案：分母2分子5)
(x+4)-(x-2)i=22-3i+yi,求x及y的值 （答案：x=18,y=-13)
實數及復數(急!!!!!)
2011-09-29 5:38 am
回答 (3)
2011-09-29 5:46 am
✔ 最佳答案
1. √125 * √50 / √1000= 5√5 * 5√2 / 10√10
= 25√10 / 10√10
= 5/2
2. (x+4) - (x-2)i = 22 - 3i + yi
(x+4) - (x-2)i = 22 + (y-3)i
x+4 = 22 --- (1)
-(x-2) = y-3 ---(2)
由(1), x = 18
代x = 18於(2)式,
-(18-2) = y-3
y = -13
參考: Knowledge is power.
2011-09-29 4:37 pm
√125×√50÷√1000
=√(25*5)×√(25*2)/√(40*25)
=5√5*5√2/5√(4*10)
=5√10/2√10
=5/2
(x+4)-(x-2)i=22-3i+yi
(x+4)-(x-2)i=22-(3-y)i
x+4=22
x=18
-(x-2)=-(3-y)
18-2=3-y
16=3-y
13=-y
y=-13
=√(25*5)×√(25*2)/√(40*25)
=5√5*5√2/5√(4*10)
=5√10/2√10
=5/2
(x+4)-(x-2)i=22-3i+yi
(x+4)-(x-2)i=22-(3-y)i
x+4=22
x=18
-(x-2)=-(3-y)
18-2=3-y
16=3-y
13=-y
y=-13
2011-09-29 4:31 pm
(a)your question=squr(125x50/1000)=squr(6.25)=2.5
(b)a+bi=c+di if and only if a=b and c=d, thus
(x+4)-(x-2)i=22+(y-3)i
thus, we have
x+4=22 => x=18
similarly, -(x-2)=y-3 put x=18=> y-3=-16 => y=-13
Simon YAU
(b)a+bi=c+di if and only if a=b and c=d, thus
(x+4)-(x-2)i=22+(y-3)i
thus, we have
x+4=22 => x=18
similarly, -(x-2)=y-3 put x=18=> y-3=-16 => y=-13
Simon YAU
參考: Simon YAU
收錄日期: 2021-04-13 18:16:00
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