SOLUTION: write the expression in standard form of a+bi :3-2i/1+2i not sure were to start i want to multiply by the conjugate but that doesnt leave me with the right form?

Algebra ->  Polynomials-and-rational-expressions -> SOLUTION: write the expression in standard form of a+bi :3-2i/1+2i not sure were to start i want to multiply by the conjugate but that doesnt leave me with the right form?      Log On


   

Question 676167: write the expression in standard form of a+bi :3-2i/1+2i not sure were to start i want to multiply by the conjugate but that doesnt leave me with the right form?
Found 2 solutions by solver91311, josmiceli:
Answer by solver91311(24713) About Me  (Show Source):
You can put this solution on YOUR website!


If by "multiply by the conjugate" you meant to multiply the given fraction by the conjugate of the denominator divided by itself, then you are doing the right thing.



What was your result?

John

Egw to Beta kai to Sigma
My calculator said it, I believe it, that settles it
The Out Campaign: Scarlet Letter of Atheism

Answer by josmiceli(19441) About Me  (Show Source):
You can put this solution on YOUR website!
+%28+3+-+2%2Ai+%29+%2F+%28+1+%2B+2%2Ai+%29+
+%28%28+3+-+2%2Ai+%29+%2F+%28+1+%2B+2%2Ai+%29%29%2A%28+1+-+2%2Ai+%29+%2F+%28+1+-+2%2Ai+%29+
Note that I am just multiplying by +a%2Fa+=+1+
+%28%28+3+-+2%2Ai+%29%2A%28+1+-+2%2Ai+%29%29+%2F+%28%28+1+-+2%2Ai+%29%2A%28+1+%2B+2i+%29%29+
+%28%28+3+-+2%2Ai+%29%2A%28+1+-+2%2Ai+%29%29+%2F+%28+1+-+4%2A%28-1%29%29+
+%28%28+3+-+2%2Ai+%29%2A%28+1+-+2%2Ai+%29%29+%2F+5+
+%28+3+-+2%2Ai+-+6%2Ai+%2B+4%2A%28-1%29+%29+%2F+5+
+%28+-1+-+8%2Ai+%29+%2F+5+
+-1%2F5+-+%288%2F5%29%2Ai+
----------------
I should be able to check by making it equal to
the original expression
+%28+3+-+2%2Ai+%29+%2F+%28+1+%2B+2%2Ai+%29+=+%28+-1+-+8%2Ai+%29+%2F+5+
+%285%2A%28+3+-+2%2Ai+%29%29+%2F+%28+1+%2B+2%2Ai+%29+=++-1+-+8%2Ai++
+%28+15+-+10%2Ai+%29+%2F+%28+1+%2B+2%2Ai+%29+=+-1+-+8%2Ai+
+15+-+10%2Ai+=+-1%2A%281+%2B+2%2Ai+%29%2A%28+1+%2B+8%2Ai+%29+
+15+-+10%2Ai+=+-1%2A%28+1+%2B+2%2Ai+%2B+8%2Ai+%2B+16%2A%28-1%29+%29+
+15+-+10%2Ai+=+-1+-+2%2Ai+-+8%2Ai+-+%28-16%29+
+15+-+10%2Ai+=+15+-+10%2Ai+
OK