ĐKXĐ: \(x\neq k.60^0;x\neq\dfrac{80^0}{7}+k.\dfrac{180^0}{7}\)
\(tan(7x+10^0)=cot3x\)
\(\Leftrightarrow tan(7x+10^0)=tan(90^0-3x)\)
\(\Leftrightarrow 7x+10^0=90^0-3x+k.180^0\)
\(\Leftrightarrow 10x=80^0+k180^0\)
\(\Leftrightarrow x=8^0+k.18^0\)
Với \(k\in Z\)
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