F.2 revision

Which of the following are identities?

• 2x + 1 = 3x - 2

• 2x + 1 = 3x - x + 1

• x² - y² = ( x - y ) ( x + y )

• ( x + y )² = x² + y²

If Ax² + 3x + 1 ≡ Bx + 1 - 2x² , then

• A = - 2 and B = 3 .

• A = 1 and B = 1 .

• A = 2 and B = 1 .

• A = 2 and B = 3 .

If x² + (A+B)x + A ≡ x² + x + 3 , then B =

• 3 .

• - 2 .

• 1 .

• - 1 .

(i) 3x + 6 = 3 ( x + 2 )

(ii) 3 ( x + 2 ) = 3x + 6

(i) is and (ii) is .

• (i) factorization , (ii) expansion

• (i) expansion , (ii) factorization

• (i) expansion , (ii) expansion

• (i) factorization , (ii) factorization

If x³ + 2x² - x - 2 is factorized, the result is ( x - 1 ) ( x + 1 ) ( x + 2 ) .

If ( x - 1 ) ( x + 1 ) ( x + 2 ) is expanded, the result is

• x³ + 2x² - x - 2 .

• 呀 Sir 無教

• 中四才學

• ( x - 1 ) ( x + 1 ) ( x + 2 )

2 m + 6 mn =

• 2m ( 3 n ) .

• 2m ( 1 + 3 n ) .

• 2m ( 1 + 6 m n ) .

• 2m ( 1 + 4 n ) .

Factorize 6 a ( m + n ) - 12 b ( m + n ) .

• 6 ( m + n ) ( a - 2 b )

• 2 ( m + n ) ( 3 a - 6 b )

• 6 ( m + n )² ( a - 2 b )

• 6 ( m + n ) ( a -6 b )

x ( a + b ) - a - b =

• ( a + b ) ( x - 1 ) .

• ( a - b ) ( x - 1 ) .

• ( a + b ) ( x + 1 ) .

• ( a - b ) ( x + 1 ) .

hk - 2 h - 2 + k =

• ( h + 1 ) ( k - 2 ) .

• ( h + 2 ) ( k - 1 ) .

• ( h - 2 ) ( k + 1 ) .

• ( h - 1 ) ( k + 2 ) .

m ( 2 a - b ) + n ( b - 2 a ) =

• ( 2 a - b ) ( m + n ) .

• ( 2 a - b ) ( m - n ) .