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1 year ago

How do I simplify the following to "a+bi" form: (1+2i)^3

Mathematics

1 answer:

damaskus [11]1 year ago

7 0

Answer:

Expand it.

(1+2i)^3 is equal to (1+2i)(1+2i)(1+2i).

Multiply everything out (being sure to multiply <em>every</em> term. (1+2i) * (1+2i) = 1+2i+2i+4i^2.

i is the square root of negative one, so i^2 is just -1. 1+2i+2i-4 is what you get from the first two, so now simplify that:

1-4 + 2i+2i = (-3+4i) and now multiply that by (1+2i):

(-3+4i) * (1+2i) = -3 - 6i +4i +8i^2.

Simplify again, and the answer is: -11-2i

Step-by-step explanation:

I hope this helps - really my only tip is don't spend time thinking about what i is, that just hurts your brain. Just remember that i^2 is equal to negative one, and treat it like regular multiplication and you will be fine.

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Select the most appropriate unit for the situation

saveliy_v [14]

Answer: Is Square feet/minute if there is two of them the second one is Cubic feet/minute

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square feet/minute would cover two-dimensional areas {walls, floors, sides of buildings, etc.}

cubic feet/minute would cover three dimensional situations {swimming pools, buckets, containers, etc.}

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2 years ago

How do you solve for u?

Paraphin [41]

Answer:

u=9.8

Step-by-step explanation:

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3 years ago

two numbered 1 to 6 dice are thrown together and their scores are added. the probability that the sum will be 4 is?

natulia [17]

Answer:

$Pr = \frac{3}{36}$

Step-by-step explanation:

Given

2 number die

Required

P(Sum = 4)

The sample space of 2 die is:

$S = \{(1, 1) (1, 2) (1, 3) (1, 4) (1, 5) (1, 6), (2, 1) (2, 2) (2, 3) (2, 4) (2, 5) (2, 6)$

$(3, 1) (3, 2) (3, 3) (3, 4) (3, 5) (3, 6), (4, 1) (4, 2) (4, 3) (4, 4) (4, 5) (4, 6)$

$(5, 1) (5, 2) (5, 3) (5, 4) (5, 5) (5, 6), (6, 1) (6, 2) (6, 3) (6, 4) (6, 5) (6, 6)$

$n(S)= 36$

The pairs that adds up to 4 are:

$Sum(4) = \{(1,3), (2,2),(3,1)\}$

$n(Sum) =3$

So, the probability is:

$Pr = \frac{n(Sum)}{n(S)}$

$Pr = \frac{3}{36}$

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2 years ago

Of every 300 magic cakes Farah makes, 90 are chocolate, what percentage of chocolate cakes Farah makes?

navik [9.2K]

Answer:

Total magic cakes =300

chocolate cakes =90

so if you want the percentage of chocolate you will divide the number of chocolate cakes over the total number of chocolates

% of chocolate cakes = 90/300×100%

=30%

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2 years ago

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kvasek [131]

Answer:

Car B has the better fuel economy.

Step-by-step explanation:

Calculate the fuel consumption for the two cars:

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Car B goes further on one L of gasoline than Car A.

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2 years ago