Algebra
Calculus
Trigonometry
Matrix
Question
Simplify the expression
−21−63i
Evaluate
(7−7i)(3−6i)
Apply the distributive property
7×3+7(−6i)−7i×3−7i(−6i)
Multiply the numbers
21+7(−6i)−7i×3−7i(−6i)
Multiply the numbers
21−42i−7i×3−7i(−6i)
Multiply the numbers
21−42i−21i−7i(−6i)
Multiply the numbers
More Steps
Evaluate
−7i(−6i)
Multiply
−7(−6)i2
Multiply
42i2
Use i2=−1 to transform the expression
42(−1)
Calculate
−42
21−42i−21i−42
Calculate
−21−42i−21i
Solution
More Steps
Evaluate
−42i−21i
Collect like terms by calculating the sum or difference of their coefficients
(−2−1)×21i
Calculate
−3×21i
Multiply the numbers
−63i
−21−63i
Show Solution
