3+4i/5-2i
show your work
2007-02-05 13:49:26 · 3 answers · asked by Jay 1 in Science & Mathematics ➔ Mathematics
3 + 4/5 i - 2i
rewrite 2i as 10/5 i
so we have 3 + (4/5 - 10/5) i
3 - 6/5 i
pull out the 3
3(1 - 2/5i)
2007-02-05 13:52:41 · answer #1 · answered by Ace 4 · 0⤊ 0⤋
Multiply by (5+2i)/(5+2i)
Which equals one so the answer doesn't change, we just get rid of the imaginary numbers in the denominator.
Now we have
(3+4i)(5+2i)/(5-2i)(5+2i)
Which equals
15+6i+20i+8i*i ALL OVER 25-(2i)^2
So (i^2 equals -1, sqrt(-1)sqrt(-1) is -1)
15+26i-8 ALL OVER 25 - (-4)
So
7+26i ALL OVER 29
Is the final answer.
Check with a graphing calculator. I'm right. =D
Edit: I'm confused. Was the problem 3 + (4i/5) - 2i? That would've been much easier... Combining like terms, booh!
2007-02-05 21:56:16 · answer #2 · answered by Anonymous · 0⤊ 0⤋
3-1.2i
2007-02-05 21:56:38 · answer #3 · answered by adilynn 1 · 0⤊ 0⤋