Thread: Roots

Show that 4+i and -4-i are the sqaure rooots of 15 +8i

Originally Posted by meli3000

Show that 4+i and -4-i are the sqaure rooots of 15 +8i

It is sufficient to show that



and that:



to show that and are square roots of . (In fact it is sufficent to show that one of these is a square root since the other is minus one times it, and so also of necessity a square root of )

RonL

Originally Posted by meli3000

Show that 4+i and -4-i are the sqaure rooots of 15 +8i

Do you know how to square a binomial?