Bài lm nek
Nhớ vote cho mk 5 sao nhá 😉
Câu 1.
A + 7x²y - 5xy² - xy = x²y + 8xy² - 5xy
-> A = (x²y + 8xy² - 5xy) - (7x²y - 5xy² - xy)
-> A = x²y + 8xy² - 5xy - 7x²y + 5xy² + xy
-> A = (8xy² + 5xy²) + (x²y - 7x²y) + (xy - 5xy)
-> A = 13xy² - 6x²y - 4xy
Câu 2.
4x² - 7x + 1 - A = 3x² - 7x - 1
-> A = (4x² - 7x + 1) - (3x² - 7x - 1)
-> A = 4x² - 7x + 1 - 3x² + 7x + 1
-> A = (4x² - 3x²) + (7x - 7x) + (1 + 1)
-> A = x² + 2
Câu 3.
5x² - 2A + 4x - 5 = A + 4x² - 6x + 7
-> A + 2A = 5x² + 4x - 5 - 4x² + 6x - 7
-> 3A = (5x² - 4x²) + (4x + 6x) + (-5 - 7)
-> 3A = x² + 10x - 12
-> 1/3. 3A = 1/3. (x² + 10x - 12)
-> A = 1/3x² + 10/3x - 4
Câu 4.
3x² - 8x + 5 - A = -2A + x² + 4x - 6
-> -A + 2A = x² + 4x - 6 - 3x² + 8x - 5
-> A = (x² - 3x²) + (4x + 8x) + (-6 - 5)
-> A = -2x² + 12x - 11
Câu 5.
4A - 3x² - 6x + 7 = x² + 3A - 4x - 3
-> 4A - 3A = x² - 4x - 3 + 3x² + 6x - 7
-> A = (x² + 3x²) + (6x - 4x) + (-3 - 7)
-> A = 4x² + 2x - 10
Câu 6.
A - (2xy - 4y²) = x² - 7y² + 5xy
-> A = (x² - 7y² + 5xy) + (2xy - 4y²)
-> A = x² - 7y² + 5xy + 2xy - 4y²
-> A = x² + (-7y² - 4y²) + (5xy + 2xy)
-> A = x² - 11y² + 7xy
Câu 7.
(6x² - 3x²y) + A = x² + y² - 2xy²
-> A = (x² + y² - 2xy²) - (6x² - 3x²y)
-> A = x² + y² - 2xy² - 6x² + 3x²y
-> A = (x² - 6x²) + y² - 2xy² + 3x²y
-> A = -5x² + y² - 2xy² + 3x²y
Câu 8.
(25u²v - 13uv² + u³) - A = 11u²v - 2u³
-> A = (25u²v - 13uv² + u³) - (11u²v - 2u³)
-> A = 25u²v - 13uv² + u³ - 11u²v + 2u³
-> A = (25u²v - 11u²v) - 13uv² + (u³ + 2u³)
-> A = 14u²v - 13uv² + 3u³
Câu 9.
x³y - 2x²y + x - y + A = x²y + 3x + 2y
-> A = (x²y + 3x + 2y) - (x³y - 2x²y + x - y)
-> A = x²y + 3x + 2y - x³y + 2x²y - x + y
-> A = -x³y + (x²y + 2x²y) + (3x - x) + (2y + y)
-> A = -x³y + 3x²y + 2x + 3y
Câu 10.
A - (2x³ - y² + 32x² - 4xy) = 10x² + 2x³
-> A = (10x² + 2x³) + (2x³ - y² + 32x² - 4xy)
-> A = 10x² + 2x³ + 2x³ - y² + 32x² - 4xy
-> A = (2x³ + 2x³) + (10x² + 32x²) - y² - 4xy
-> A = 4x³ + 42x² - y² - 4xy
