1： (X & sup2; + 1) y & sup2; - X & sup2; - 1 2： - 49x & sup2; + 14x-1 + Y & sup2;

1： (X & sup2; + 1) y & sup2; - X & sup2; - 1 2： - 49x & sup2; + 14x-1 + Y & sup2;

1： (X & # 178; + 1) y & # 178; - X & # 178; - 1 = x & # 178; Y & # 178; - X & # 178; + Y & # 178; - 1 = x & # 178; (Y & # 178; - 1) + (Y & # 178; - 1)
=（x²-1)(y²-1)=(x+1)(x-1)(y+1)(y-1)
2： - 49x & # 178; + 14x-1 + Y & # 178;
=y²-(49x²-14x+1)=y²-((7x)²-14x+1)
=y²-(7x-1)²
=(y+7x-1)(y-7x+1)

Factorization (very simple, but I can't)
x^2+3x+2=(x+1)(x+2x)
This is a correct factorization, but I forgot the specific process
The brother wrote out the process

X ^ 2 + 3x + 2 = (x + 1) (x + 2), it should be this~
Cross multiplication~
x^2+2+3x
1 1
1 2
The constant 2 = 1 * 2,1 + 2 = 3, that is 3x coefficient 3
And the coefficient of x ^ 2 is 1 = 1 * 1, so the coefficient of X in the two brackets is 1
That is, the original formula = (x + 1) (x + 2)

Junior one math factorization problem a ~ very simple '~ ~ help ~ in urgent need of ah!
If a + B = 1, a-2b = 3, find the value of a ^ 2 - ab - 2b ^ 2

a^2 -ab -2b^2
=(a+b)(a-2b)
=1*3
=3