a, 5x-4 /2 +4x+4/9 b, x^2y-6/2x^2y+6-xy^2/2x^2y c, 4x-1/3xy^2-7x-1/3xy^2
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126 Tham khảo câu trả lời từ Trợ lý ảo Lazi a) To simplify the expression, we need to find a common denominator for the fractions. The common denominator for 2 and 9 is 18. So, we have: (5x - 4)/2 + (4x + 4)/9 To get the fractions to have a common denominator of 18, we need to multiply the first fraction by 9/9 and the second fraction by 2/2: (9(5x - 4))/18 + (2(4x + 4))/18 Simplifying further: (45x - 36)/18 + (8x + 8)/18 Now, we can combine the fractions: (45x - 36 + 8x + 8)/18 Combining like terms: (53x - 28)/18 So, the simplified expression is (53x - 28)/18. b) To simplify the expression, we need to find a common denominator for the fractions. The common denominator for 2x^2y + 6 and 2x^2y is 2x^2y(2x^2y + 6). So, we have: (x^2y - 6)/(2x^2y + 6) - (xy^2)/(2x^2y) To get the fractions to have a common denominator of 2x^2y(2x^2y + 6), we need to multiply the first fraction by (2x^2y)/(2x^2y) and the second fraction by (2x^2y + 6)/(2x^2y + 6): ((x^2y - 6)(2x^2y))/((2x^2y + 6)(2x^2y)) - ((xy^2)(2x^2y + 6))/((2x^2y)(2x^2y + 6)) Simplifying further: (2x^4y^2 - 12x^2y)/((2x^4y^2 + 6x^2y)(2x^2y)) - (2x^3y^3 + 6xy^2)/((2x^4y^2 + 6x^2y)(2x^2y)) Now, we can combine the fractions: (2x^4y^2 - 12x^2y - 2x^3y^3 - 6xy^2)/((2x^4y^2 + 6x^2y)(2x^2y)) So, the simplified expression is (2x^4y^2 - 12x^2y - 2x^3y^3 - 6xy^2)/((2x^4y^2 + 6x^2y)(2x^2y)). c) To simplify the expression, we need to find a common denominator for the fractions. The common denominator for 3xy^2 and 3xy^2 is 3xy^2. So, we have: (4x - 1)/(3xy^2) - (7x - 1)/(3xy^2) Since the fractions already have a common denominator, we can combine them directly: (4x - 1 - 7x + 1)/(3xy^2) Combining like terms: (-3x)/(3xy^2) Simplifying further: -1/y^2 So, the simplified expression is -1/y^2.