Question

) (a+b) +(a-b): 2) 3(2-a +4 (a-5). 3) (x-1)^3-(x+1)^3. 4) -(3+x)^2+(1-x)^2​

Answer 1

1. (a+b)+(a-b)=a+b+a-b=2a
2. 3(2-a+4(a-5)=3(2-a+4a-20)=3(3a-18)=9a-54
3. (x-1)³- (x+1)³= x³-3x²+3x-1-x³-3x²-3x-1=-3x²-1-3x²-1=-6x²-2
4. -(3+x)²+(1-x)²=-(9+6x+x²)+1-2x+x²=-9-6x-x²+1-2x+x²=-8x-8