i know the answer is 4...i just don't know why.
2007-06-05 14:16:19 · 6 answers · asked by Jenna 2 in Science & Mathematics ➔ Mathematics
2+3i, 2-3i
Sum = 2+3i+2-3i = 4
2007-06-05 14:22:47 · answer #1 · answered by Kemmy 6 · 0⤊ 0⤋
2+3i + 2-3i = 4
2016-05-17 15:22:42 · answer #2 · answered by margit 3 · 0⤊ 0⤋
If one root is 2+3i, the other is 2-3i, so the
sum of the roots is 4.
This follows directly from the quadratic formula.
2007-06-05 15:02:44 · answer #3 · answered by steiner1745 7 · 0⤊ 0⤋
for ax^2 + bx + c = 0
...-b/c = sum of the roots
do -b/c using whatever you got to get the sum..
you havent provided enough information to solve this problem, but if 2+3i + the other root = 4, then the other root would be 2 - 3i
if you wouldnt know the answer(duh) then use the quadratic formula if given to you, and use the -b/c to just get yourself 4.
2007-06-05 14:25:57 · answer #4 · answered by Anonymous · 0⤊ 0⤋
If a quadratic equation with real coefficients has a complex root (a+bi), then the other root is the complex conjugate (a-bi). So the sum of the roots is a+bi+a-bi = 2a. In your example, 2a=2(2)=4.
2007-06-05 14:25:14 · answer #5 · answered by TFV 5 · 0⤊ 0⤋
don't know and don't care
2007-06-05 14:20:47 · answer #6 · answered by cynthia o 2 · 0⤊ 2⤋