Expand: (1 + x)(2 - x)?

Well there r actually 2 ways of solving this easily,
1) Use the formula
(a + x)(b - x) = ab + (b - a)x - x² [ In this formula, a and b are constants and x is variable ]
(1 + x)(2 - x) = (1)(2) + (2 - 1)x - x²
(1 + x)(2 - x) = [ 2 + x - x² ]
2) Use FOIL
(1 + x)(2 - x)
1(2 - x) + x(2 - x)
2 - x + 2x - x²
[ 2 + x - x² ]
So x = - 1 , + 2
hope i helped

(1+x)(2-x)

expansion means opening up the brackets to get the simplest answer with no brackets

1*2 +1*(-x) + x*2 + x*(-x)

2 - x + 2x - x^2

that's the expansion

to solve it, you set the whole thing = 0

2 - x + 2x - x^2 = 0

x^2 - 2x + x - 2 =

x^2 - x - 2 = 0

x^2 - 2x + x - 2 =

x(x -2 ) + 1(x-2) = 0

(x+1)(x-2) = 0


thus; either x + 1 = 0 or x -2 = 0
and so x = -1 , x = 2

x=-1
and
x=2

Expanding (1+x)(2-x)

= 1(2-x) + x(2-x)

= 2 - x + 2x - x^2

= 2 + x - x^2

Solving for zero, we have (1+x)(2-x) = 0

==> x = -1 or 2

2-x+2x-x2
so its
2+ x- x^2
and the solution is x= -1 or x= 2

(1 + x)(2 - x)
= 1(2) - 1(x) + x(2) - x(x)
= 2 - x + 2x - x^2
= -x^2 + x + 2

(1 + x) (2 - x) = 0
2 + 2x - x - x^2 = 0
2 + x - x^2 = 0
x^2 - x - 2 = 0
(x - 2)(x + 1) = 0

x = 2 or -1

================================
(1 + x)(2 - x)
2 + 2x - x - x^2
2 + x - x^2




Rohn

You do not have to expand.

x = - 1 , x = 2-----from given equation.

-X'2+X+2

also X=-1 and X=2

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