1)
a)
22p^4·g² = 2·g
99p^5·g 3·p
б)
7a = 7a = 7
a²+5a a(a+5) a+5
в)
y²-z² = (y-z)(y+z) = y-z
2y+2z 2(y+z) 2
г)
a²-1 =(a-1)(a+1) =a+1
a²-2a+1 (a-1)² a-1
2)
a) y-20 - 5y-2 = y(y-20) -4(5y-2) = y²-20y-20y+8 =y²-40y+8
4y y² 4y² 4y² 4y²
б) 1 - 1 = (5c+d)-(5c-d) =5c+d-5c+d = 2d
5c-d 5c+d (5c-d)(5c+d) (5c-d)(5c+d) 25c²-d²
в) 7 + 7a-3 = 7 + 7a-3 = 7a+7a-3 = 14a-3
a+5 a²+5a a+5 a(a+5) a(a+5) a²+5a
3)
1 - 2 + 3 = (x-2)(x-1)-2(x²-1)+3(x-2) = x²-x-2x+2-2x²+2+3x-6 =
x+1 x-2 x²-1 (x-1)(x+1)(x-2) (x-1)(x+1)(x-2)
= -x²-2 =- (x²+2)
(x²-1)(x-2) (x²-1)(x-2)
4)
1 + 3в² + 3 = 1 - 3в² + 3 =
в-3 27-в³ в³+3в+9 в-3 (в-3)( в²+3в+9) в²+3в+9
= в²+3в+9-3в²+3в-9 = -2в²+6в = -2в(в-3) =-2в
(в-3)(в²+3в+9) (в-3)(в²+3в+9) (в-3)(в²+3в+9) в²+3в+9
в=2,5
-2×2,5 = -5 = -5 =-1 =-20
2,5²+3×2,5+9 6,25+7,5+9 22,75 4,55 91