Question

Multiply (2 - 71)(-1 + 41)? 26 + 151 -2 - 281 26 + i -30 + 151

Answer 1

For this case we must simplify the following expression:

$(2-7i) (- 1 + 4i)$

Applying distributive property we have:

$(2) (- 1) + (2) (4i) + (- 7i) (- 1) + (- 7i) (4i) =$

We have to:

$+ * - = -\\- * - = +$

So:

$-2 + 8i + 7i-28i ^ 2 =$

We add similar terms:

$-2 + 15i-28i ^ 2 =$

By definition we have:$i ^ 2 = -1$

$-2 + 15i-28 (-1) =\\-2 + 15i + 28 =$

Different signs are subtracted and the sign of the major is placed:

$26 + 15i$

Answer:

$26 + 15i$