SOLUTION: Hello there, I am currently working on an optional summer packet for school, and I came across this problem. I have the answer available to me, but I don't understand how to get t

Algebra ->  Radicals -> SOLUTION: Hello there, I am currently working on an optional summer packet for school, and I came across this problem. I have the answer available to me, but I don't understand how to get t      Log On


   



Question 149991: Hello there,
I am currently working on an optional summer packet for school, and I came across this problem. I have the answer available to me, but I don't understand how to get the answer. If you could explain to me how to simplify this expression, I'd greatly appreciate it.
(+sqrt%28+3+%29+ + 4i+sqrt%28+2+%29+)(+sqrt%28+3+%29+ - 4i+sqrt%28+2+%29+)
Thank you!

Answer by nerdybill(7384) About Me  (Show Source):
You can put this solution on YOUR website!
If you had:
(a-b)(a+b)
Applying "FOIL", you get:
a^2 + ab - ab - b^2
Notice how ab's cancel leaving:
a^2 - b^2
.
In your problem:
a = +sqrt%283%29+
b = +4i%2Asqrt%282%29+
.
a^2 = 3
b^2 = -16(2) = -32
.
Therefore,
a^2 - b^2 = 3 - (-32) = 3 + 32 = 34