下列各运算中,计算正确的是 ( )
a 2 · 2 a 2 = 2 a 4
x 8 ÷ x 2 = x 4
( x - y ) 2 = x 2 - xy + y 2
( - 3 x 2 ) 3 = - 9 x 6
下列计算正确的是 ( )
8 a - a = 7
a 2 + a 2 = 2 a 4
2 a · 3 a = 6 a 2
a 6 ÷ a 2 = a 3
下列运算,正确的是 ( )
a ( - a ) = - a 2
( a 2 ) 3 = a 5
2 a - a = 1
a 2 + a = 3 a
3 ab - 2 ab = 1
( 3 a 2 ) 2 = 9 a 4
3 a 2 · 2 a = 6 a 2
下列运算正确的是 ( )
a · a 2 = a 2
5 a · 5 b = 5 ab
a 5 ÷ a 3 = a 2
2 a + 3 b = 5 ab
以下计算正确的是 ( )
( - 2 a b 2 ) 3 = 8 a 3 b 6
3 ab + 2 b = 5 ab
( - x 2 ) · ( - 2 x ) 3 = - 8 x 5
2 m ( m n 2 - 3 m 2 ) = 2 m 2 n 2 - 6 m 3
3 a × 2 a = 6 a
a 8 ÷ a 4 = a 2
- 3 ( a - 1 ) = 3 - 3 a
( 1 3 a 3 ) 2 = 1 9 a 9
下列计算错误的是 ( )
( a 3 b ) · ( a b 2 ) = a 4 b 3
( - m n 3 ) 2 = m 2 n 6
a 5 ÷ a - 2 = a 3
x y 2 - 1 5 x y 2 = 4 5 x y 2
a 6 + a 6 = 2 a 12
2 - 2 ÷ 2 0 × 2 3 = 32
( - 1 2 a b 2 ) · ( - 2 a 2 b ) 3 = a 3 b 3
a 3 · ( - a ) 5 · a 12 = - a 20
计算 3 a 2 · a 3 的结果是 ( )
4 a 5
4 a 6
3 a 5
3 a 6
a 2 + a 3 = a 5
3 a 2 · 4 a 3 = 12 a 6
5 3 - 3 = 5
2 × 3 = 6
下列运算中,正确的是 ( )
3 y + 5 y = 8 y 2
3 y - 5 y = - 2
3 y × 5 y = 15 y 2
3 y ÷ 5 y = 3 5 y
( - 1 3 ) 2 = 9
2018 0 - - 8 3 = - 1
3 a 3 · 2 a - 2 = 6 a ( a ≠ 0 )
18 - 12 = 6
2 a × 3 a = 5 a
( - 2 a ) 3 = - 6 a 3
6 a ÷ 2 a = 3 a
( - a 3 ) 2 = a 6
2 x · 3 x = 6 x
3 x - 2 x = x
( 2 x ) 2 = 4 x
( x 2 ) 4 = x 6