(A+B)^2=A^2+2AB+B^2
sqrt(A)^2=A
(-A)^2 = A^2
See if you can get further with these hints.
Okay, I have the first step, but after that, they ask me to expand and I'm not sure where they're getting the next numbers from.
Original question:
(-3- sqrt(-7))^2
Now, my first step should be:
(-3-i sqrt(7))^2
After that, I'm lost. I see what they're doing after that, but I don't know where the numbers are coming from or how to recreate the answer.
Help, please. :)
Thank you!
3 answers
I still don't see where it's coming from. I'm sorry. :)
(-3-iā7)^2
= 9 + 6iā7 + i^2(7) , but i^2 = -1
= 9 + (6ā7)i - 7
= 2 + (6ā7)i
Notice I followed exactly the steps that MathMate had outlined for you.
= 9 + 6iā7 + i^2(7) , but i^2 = -1
= 9 + (6ā7)i - 7
= 2 + (6ā7)i
Notice I followed exactly the steps that MathMate had outlined for you.