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How do you simplify #(-2+5i)(-1+4i)#?

Answer 1

Cora Alexander

#-18 - 13i#

#(-2*5i)(-1+4i)#

Use FOIL to distribute: #-2 * -1 = 2#

#-2 * 4i = -8i#

#5i * -1 = -5i#

#5i * 4i = 20i^2#

Combine them together: #2 - 8i - 5i + 20i^2#

Combine like terms: #2 - 13i + 20i^2#

We know that #i^2 = -1#, so: #2 - 13i + 20(-1)#

#2 - 13i - 20#

Simplify: #-18 - 13i#

Hope this helps!

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Answer 2

Elijah Allen

To simplify ((-2+5i)(-1+4i)), use the distributive property to multiply each term of the first complex number by each term of the second complex number. Then combine like terms and simplify the expression.

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Answer from HIX Tutor

When evaluating a one-sided limit, you need to be careful when a quantity is approaching zero since its sign is different depending on which way it is approaching zero from. Let us look at some examples.