Answer:

Step-by-step explanation:
![(x+1-i)(x+1+i)\\\\=(x+1)^2 -i^2~~~~~~~~~~~~~;[a^2 -b^2 = (a+b)(a-b)]\\\\=x^2 +2x +1 -(-1)\\\\=x^2 +2x +1+1\\\\=x^2 +2x +2](https://tex.z-dn.net/?f=%28x%2B1-i%29%28x%2B1%2Bi%29%5C%5C%5C%5C%3D%28x%2B1%29%5E2%20-i%5E2~~~~~~~~~~~~~%3B%5Ba%5E2%20-b%5E2%20%3D%20%28a%2Bb%29%28a-b%29%5D%5C%5C%5C%5C%3Dx%5E2%20%2B2x%20%2B1%20-%28-1%29%5C%5C%5C%5C%3Dx%5E2%20%2B2x%20%2B1%2B1%5C%5C%5C%5C%3Dx%5E2%20%2B2x%20%2B2)
Answer:
n = -7,6
Step-by-step explanation:
n(n+1)+3=45
distributive property: a(b+c) = ab+ac
n²+n+3 = 45
n²+n -42 = 0
factor now
(n+7)(n-6) = 0
n = -7,6
Answer:
297 cubic centimeters
Step-by-step explanation:
volume is LWH
11*9*3 = 297
Answer:
-9,4
Step-by-step explanation: