2x /x^2 + 2xy – y /2y^2-xy + 4 /x^2-4y^2 11/08/2021 Bởi Natalia 2x /x^2 + 2xy – y /2y^2-xy + 4 /x^2-4y^2
Đáp án: `\frac{3x-2y+4}{x^2-4y^2}` Giải thích các bước giải: `\frac{2x}{x^2+2xy}-\frac{y}{2y^2-xy}+\frac{4}{x^2-4y^2}` `=\frac{2x}{x(x+2y)}-\frac{y}{y(2y-x)}+\frac{4}{(x-2y)(x+2y)}` `=\frac{2}{x+2y}-\frac{1}{2y-x}+\frac{4}{(x-2y)(x+2y)}` `=\frac{2}{x+2y}+\frac{1}{x-2y}+\frac{4}{(x-2y)(x+2y)}` `=\frac{2(x-2y)+(x+2y)+4}{(x+2y)(x-2y)}` `=\frac{2x-4y+x+2y+4}{(x+2y)(x-2y)}` `=\frac{3x-2y+4}{x^2-4y^2}` Bình luận
Đáp án: `\frac{3x-2y+4}{x^2-4y^2}`
Giải thích các bước giải:
`\frac{2x}{x^2+2xy}-\frac{y}{2y^2-xy}+\frac{4}{x^2-4y^2}`
`=\frac{2x}{x(x+2y)}-\frac{y}{y(2y-x)}+\frac{4}{(x-2y)(x+2y)}`
`=\frac{2}{x+2y}-\frac{1}{2y-x}+\frac{4}{(x-2y)(x+2y)}`
`=\frac{2}{x+2y}+\frac{1}{x-2y}+\frac{4}{(x-2y)(x+2y)}`
`=\frac{2(x-2y)+(x+2y)+4}{(x+2y)(x-2y)}`
`=\frac{2x-4y+x+2y+4}{(x+2y)(x-2y)}`
`=\frac{3x-2y+4}{x^2-4y^2}`