Giải hôk mik nha ! 6x+5/7<4x+7 8x+3/2<2x+5 15x+2>2x+1/3 2(x+4)<3x-14/2 X/3+x-2/5>4-3x/-2x 24/07/2021 Bởi Samantha Giải hôk mik nha ! 6x+5/7<4x+7 8x+3/2<2x+5 15x+2>2x+1/3 2(x+4)<3x-14/2 X/3+x-2/5>4-3x/-2x
Giải thích các bước giải: \(\begin{array}{l} a)6x + \frac{5}{7} < 4x + 7 \\ \Leftrightarrow 2x < \frac{{44}}{7} \\ \Leftrightarrow x < \frac{{22}}{7} \\ b)8x + \frac{3}{2} < 2x + 5 \\ \Leftrightarrow 6x < \frac{7}{2} \\ \Leftrightarrow x < \frac{7}{{12}} \\ c)15x + 2 > 2x + \frac{1}{3} \\ \Leftrightarrow 13x > \frac{{ – 5}}{3} \\ \Leftrightarrow x > \frac{{ – 5}}{{39}} \\ d)2(x + 4) < 3x – \frac{{14}}{2} \\ \Leftrightarrow 2x + 8 < 3x – \frac{{14}}{2} \\ \Leftrightarrow x > 15 \\ e)\frac{x}{3} + \frac{{x – 2}}{5} > \frac{{4 – 3x}}{{ – 2x}} \\ ĐK:x \ne 0 \\ \Leftrightarrow \frac{{5x + 3x – 6}}{{15}} > \frac{{3x – 4}}{{2x}} \\ \Leftrightarrow \frac{{8x – 6}}{{15}} – \frac{{3x – 4}}{{2x}} > 0 \\ \Leftrightarrow \frac{{16x^2 – 12x – 45x + 60}}{{30x}} > 0 \\ \Leftrightarrow \frac{{16x^2 – 57x + 60}}{{30x}} > 0 \\ \Leftrightarrow 30x > 0(do:16x^2 – 57x + 60 > 0) \\ \Leftrightarrow x > 0 \\ \end{array}\) Bình luận
Đáp án:
Giải thích các bước giải:
Giải thích các bước giải:
\(
\begin{array}{l}
a)6x + \frac{5}{7} < 4x + 7 \\
\Leftrightarrow 2x < \frac{{44}}{7} \\
\Leftrightarrow x < \frac{{22}}{7} \\
b)8x + \frac{3}{2} < 2x + 5 \\
\Leftrightarrow 6x < \frac{7}{2} \\
\Leftrightarrow x < \frac{7}{{12}} \\
c)15x + 2 > 2x + \frac{1}{3} \\
\Leftrightarrow 13x > \frac{{ – 5}}{3} \\
\Leftrightarrow x > \frac{{ – 5}}{{39}} \\
d)2(x + 4) < 3x – \frac{{14}}{2} \\
\Leftrightarrow 2x + 8 < 3x – \frac{{14}}{2} \\
\Leftrightarrow x > 15 \\
e)\frac{x}{3} + \frac{{x – 2}}{5} > \frac{{4 – 3x}}{{ – 2x}} \\
ĐK:x \ne 0 \\
\Leftrightarrow \frac{{5x + 3x – 6}}{{15}} > \frac{{3x – 4}}{{2x}} \\
\Leftrightarrow \frac{{8x – 6}}{{15}} – \frac{{3x – 4}}{{2x}} > 0 \\
\Leftrightarrow \frac{{16x^2 – 12x – 45x + 60}}{{30x}} > 0 \\
\Leftrightarrow \frac{{16x^2 – 57x + 60}}{{30x}} > 0 \\
\Leftrightarrow 30x > 0(do:16x^2 – 57x + 60 > 0) \\
\Leftrightarrow x > 0 \\
\end{array}
\)