Question
Simplify the expression
−21−i
Evaluate
(4−2i)(1×i)3−4i
Remove the parentheses
(4−2i)×1×i3−4i
Multiply the terms
More Steps

Multiply the terms
(4−2i)×1×i
Rewrite the expression
(4−2i)i
Apply the distributive property
4i−2i×i
Multiply the numbers
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Evaluate
−2i×i
Multiply
−2i2
Use i2=−1 to transform the expression
−2(−1)
Calculate
2
4i+2
Reorder the terms
2+4i
2+4i3−4i
Multiply by the Conjugate
(2+4i)(2−4i)(3−4i)(2−4i)
Calculate
More Steps

Evaluate
(3−4i)(2−4i)
Apply the distributive property
3×2+3(−4i)−4i×2−4i(−4i)
Multiply the numbers
6+3(−4i)−4i×2−4i(−4i)
Multiply the numbers
6−12i−4i×2−4i(−4i)
Multiply the numbers
6−12i−8i−4i(−4i)
Multiply the numbers
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Evaluate
−4i(−4i)
Multiply
−4(−4)i2
Multiply
16i2
Use i2=−1 to transform the expression
16(−1)
Calculate
−16
6−12i−8i−16
Calculate
−10−12i−8i
Multiply the numbers
More Steps

Evaluate
−12i−8i
Collect like terms by calculating the sum or difference of their coefficients
(−3−2)×4i
Calculate
−5×4i
Multiply the numbers
−20i
−10−20i
(2+4i)(2−4i)−10−20i
Calculate
More Steps

Evaluate
(2+4i)(2−4i)
Use (a+b)(a−b)=a2−b2 to simplify the product
22−(4i)2
Evaluate the power
4−(4i)2
Evaluate the power
More Steps

Evaluate
(4i)2
Evaluate
42i2
Evaluate the power
16i2
Evaluate the power
−16
4−(−16)
Calculate
20
20−10−20i
Rewrite the expression
2010(−1−2i)
Cancel out the common factor 10
2−1−2i
Use b−a=−ba=−ba to rewrite the fraction
−21+2i
Solution
−21−i
Show Solution
