Rút gọn biểu thức B=(x+1/2x-2+3/x^2-1-x+3/2x+2).4x^2-4/5 27/08/2021 Bởi Skylar Rút gọn biểu thức B=(x+1/2x-2+3/x^2-1-x+3/2x+2).4x^2-4/5
`B=(\frac{x+1}{2x-2}+\frac{3}{x^2-1}-\frac{x+3}{2x+2}).\frac{4x^2-4}{5}` `(x ne ±1)` `B=(\frac{x+1}{2(x-1)}+\frac{3}{(x-1)(x+1)}-\frac{x+3}{2(x+1)}).\frac{4(x^2-1)}{5}` `B=\frac{(x+1)^2+3.2-(x+3)(x-1)}{2(x-1)(x+1)}.\frac{4(x-1)(x+1)}{5}` `B=\frac{x^2+2x+1+6-x^2+x-3x+3}{2} . 4/5` `B=10/2 . 4/5` `B=4` Bình luận
Đáp án: Giải thích các bước giải: 2x+2≠0 2x−2≠0 x1−1≠0 {2x+2≠02x−2≠0x1−1≠0 ⇔x≠−1x≠1x≠±1⇔{x≠−1x≠1x≠±1 Vậy, ĐK: x≠±1x≠±1 b. (x+1/2x−2+ 3/x^2−1− x+3/2x+2).4x^2−4/5 (x+12x−2+3×2−1−x+32x+2).4×2−45 ⇔((x+1)(x+1)+6−(x+3)(x−1) /2(x2−1).4x2−4/5 ⇔(x^2+2x+1+6−x^2+x−3x+3 /2(x2−1).4(x2−1)/5 ⇔10.4/10=4 Chúc bn hok tốt # Yukisanumi~ Bình luận
`B=(\frac{x+1}{2x-2}+\frac{3}{x^2-1}-\frac{x+3}{2x+2}).\frac{4x^2-4}{5}` `(x ne ±1)`
`B=(\frac{x+1}{2(x-1)}+\frac{3}{(x-1)(x+1)}-\frac{x+3}{2(x+1)}).\frac{4(x^2-1)}{5}`
`B=\frac{(x+1)^2+3.2-(x+3)(x-1)}{2(x-1)(x+1)}.\frac{4(x-1)(x+1)}{5}`
`B=\frac{x^2+2x+1+6-x^2+x-3x+3}{2} . 4/5`
`B=10/2 . 4/5`
`B=4`
Đáp án:
Giải thích các bước giải:
2x+2≠0
2x−2≠0
x1−1≠0
{2x+2≠02x−2≠0x1−1≠0
⇔x≠−1x≠1x≠±1⇔{x≠−1x≠1x≠±1
Vậy, ĐK: x≠±1x≠±1
b. (x+1/2x−2+ 3/x^2−1− x+3/2x+2).4x^2−4/5
(x+12x−2+3×2−1−x+32x+2).4×2−45
⇔((x+1)(x+1)+6−(x+3)(x−1) /2(x2−1).4x2−4/5
⇔(x^2+2x+1+6−x^2+x−3x+3 /2(x2−1).4(x2−1)/5
⇔10.4/10=4
Chúc bn hok tốt
# Yukisanumi~