I'm really confused. What I have so far is..
(2 + i square root 3)( -1 + 2i square root 3)
and that's about it. I know that I have to F.O.I.L., but I don't understand how to do it when there are square roots involved.
(2 + i square root 3)( -1 + 2i square root 3)
and that's about it. I know that I have to F.O.I.L., but I don't understand how to do it when there are square roots involved.
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Square roots multiply in FOIL just like other items do.
First: 2 * -1 = -2
Outside: 2 * 2i sqrt(3) = 4isqrt(3)
Inside: i sqrt(3) * -1 = -i sqrt(3)
Last: i sqrt(3) * 2i sqrt(3) = (i * 2i)[(sqrt(3) * sqrt(3)] = 2i^2 * 3 = 2(-1) * 3 = -6
Combine into:
-2 - 6 + 4i sqrt(3) - i sqrt(3)
Combine like terms:
-8 + 3i sqrt(3) [or perhaps preferably -8 + 3sqrt(3) i]
First: 2 * -1 = -2
Outside: 2 * 2i sqrt(3) = 4isqrt(3)
Inside: i sqrt(3) * -1 = -i sqrt(3)
Last: i sqrt(3) * 2i sqrt(3) = (i * 2i)[(sqrt(3) * sqrt(3)] = 2i^2 * 3 = 2(-1) * 3 = -6
Combine into:
-2 - 6 + 4i sqrt(3) - i sqrt(3)
Combine like terms:
-8 + 3i sqrt(3) [or perhaps preferably -8 + 3sqrt(3) i]
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(2 + i square root 3)( -1 + 2i square root 3) =
-2-isqrt3+4isqrt3+2i^2(sqrt3)^2=
(remember i^2=-1, and (sqrt3)^2=3
-2+3isqrt3-2x3=
-8+3isqrt3
-2-isqrt3+4isqrt3+2i^2(sqrt3)^2=
(remember i^2=-1, and (sqrt3)^2=3
-2+3isqrt3-2x3=
-8+3isqrt3
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(2+sqrt(-3))(-1+sqrt(-12))
=-2+2sqrt(-12)-sqrt(-3)+sqrt(-3)sqrt(-…
=-2+2i*sqrt(12)-i*sqrt(3)+i*sqrt(3)*i*…
=-2+4i*sqrt(3)-i*sqrt(3)+i^2*6
=-2+3i*sqrt(3)+i^2*6
=-2+3i*sqrt(3)-6
=-8+3*sqrt(3)i
=-2+2sqrt(-12)-sqrt(-3)+sqrt(-3)sqrt(-…
=-2+2i*sqrt(12)-i*sqrt(3)+i*sqrt(3)*i*…
=-2+4i*sqrt(3)-i*sqrt(3)+i^2*6
=-2+3i*sqrt(3)+i^2*6
=-2+3i*sqrt(3)-6
=-8+3*sqrt(3)i
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multiply to get -2 +4i.square root(3) -i.square root(3) -2.3
-8 + 3i.square root(3)
-8 + 3i.square root(3)