Cộng lần lượt với 1 bạn nhé (x2-27)/2+1+(x2-29)/4+1=(x2-31)/6+1+(x2-32)/7+1
(x2-25)/2+(x2-25)/4=(x2-25)/6+(x2-25)/7
(x2-25)/2+(x2-25)/4-(x2-25)/6-(x2-25)/7=0
(x2-25)(1/2+1/4-1/6-1/7)=0
(x2-25)37/84=0
=>x2-25=0
<=>x2=25
<=>x=-5 hoặc 5
\(\Leftrightarrow\frac{x^2-27}{2}+1+\frac{x^2-29}{4}+1=\frac{x^2-31}{6}+1+\frac{x^2-32}{7}+1\)
\(\Leftrightarrow\frac{x^2-25}{2}+\frac{x^2-25}{4}-\frac{x^2-25}{6}-\frac{x^2-25}{7}=0\)
\(\Leftrightarrow\left(x^2-25\right)\left(\frac{1}{2}+\frac{1}{4}-\frac{1}{6}-\frac{1}{7}\right)=0\)
\(\Leftrightarrow x^2-25=0\)
\(\Leftrightarrow\int^{x=5}_{x=-5}\)
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