下列运算,正确的是 ( )
2 x + 3 y = 5 xy
( x - 3 ) 2 = x 2 - 9
( x y 2 ) 2 = x 2 y 4
x 6 ÷ x 3 = x 2
下列运算正确的是 ( )
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
( a 2 ) 3 = a 5
3 a 2 + a = 3 a 3
a 5 ÷ a 2 = a 3 ( a ≠ 0 )
a ( a + 1 ) = a 2 + 1
a 6 ÷ a 3 = a 3
a 4 · a 2 = a 8
( 2 a 2 ) 3 = 6 a 6
a 2 + a 2 = a 4
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 2 · a 3 = a 6
a 3 - a 2 = a
a 3 ÷ a 2 = a
( - a 3 ) 2 = - a 6
a 8 ÷ a 2 = a 4
3 a 2 - 2 a 2 = a 2
下列计算正确的是 ( )
x 2 + x 3 = x 5
x 2 · x 3 = x 6
x 3 ÷ x 2 = x
( 2 x 2 ) 3 = 6 x 6
下列各式中,计算正确的是 ( )
a 3 · a 2 = a 6
a 3 + a 2 = a 5
a 6 ÷ a 3 = a 2
( a 3 ) 2 = a 6
下列各式计算正确的是 ( )
x + x 2 = x 3
( x 2 ) 3 = x 5
x 6 ÷ x 2 = x 3
x · x 2 = x 3
下列运算中正确的是 ( )
a 5 + a 5 = a 10
a 7 ÷ a = a 6
下列计算结果是 x 5 的为 ( )
x 10 ÷ x 2
x 2 · x 3
( x 2 ) 3
x 6 - x
a 2 + a 3 = a 5
a 8 ÷ a 4 = a 4
( - 2 ab ) 2 = - 4 a 2 b 2
( a + b ) 2 = a 2 + b 2
下列四个算式中,正确的是 ( )
a + a = 2 a
a 5 ÷ a 4 = 2 a
( a 5 ) 4 = a 9
a 5 - a 4 = a