« Знайди помилку» -2а2 + (10а – 1) = -2а2 + 10а – 1
12х3 + 4х2 – (4х – 2) = 12х3 + 4х2 – 4х – 2
- 5a3b + (3ab – 5ab2) –5ab = - 5a3b + 3ab – 5ab2 – 5ab
-4b2 – (9с2 + 2aс) – (3b2 – ас) =-4b2 + 9с2 + 2aс + 3bс – ас -
х3 –( х2 – 10) = х3 + х2 – 10
3х5 – 2х3 +( х2 – 2х) – 5 = 3х5 + 2х3 + х2 – 2х + 5
8a2c –( 7a2c2 – 7a2c2 + c )– 16 = 8a2c – 14a2c2 + c + 16
решить
= (4b+a)(3a²b² + 4b- a)
2) 49c² -14c+1 -21ac+3a = (49c²-14c+1) -3a(7c - 1) = (7c - 1)² - 3a(7c - 1) =
=(7c-1)(7c - 1 - 3a)
3)ax²+ay²+x^4+2x²y²+y^4 = a(x²+y²)+(x^4+2x²y²+y^4) = a(x²+y²) +(x²+y²)²=
= (x²+y²) (a +x²+y²)
4) 27c³-d³+9c²+3cd+d² = [(3c)³-d³]+ (9c²+3cd+d²) =
=[(3c - d)(9c²+3cd+d²)] + (9c²+3cd+d²) = (9c²+3cd+d²) (3c-d+1)
5) b³-2b²-2b+1 =(b³ + 1) - 2b( b+1) = (b+1)(b² -b+1) - 2b(b+1) =
= (b+1)(b² -b+1-2b) = (b+1)(b² -3b+1)