[tex]\dfrac{\cot x}{1+\csc x}=\dfrac{\csc x-1}{\cot x}\\\\L_s=\dfrac{\cos x}{\sin x}:\left(1+\dfrac{1}{\sin x}\right)=\dfrac{\cos x}{\sin x}:\left(\dfrac{\sin x}{\sin x}+\dfrac{1}{\sin x}\right)\\\\=\dfrac{\cos x}{\sin x}:\dfrac{\sin x+1}{\sin x}=\dfrac{\cos x}{\sin x}\cdot\dfrac{\sin x}{\sin x+1}=\dfrac{\cos x}{\sin x+1}[/tex]
[tex]R_s=\left(\dfrac{1}{\sin x}-1\right):\dfrac{\cos x}{\sin x}=\left(\dfrac{1}{\sin x}-\dfrac{\sin x}{\sin x}\right)\cdot\dfrac{\sin x}{\cos x}\\\\=\dfrac{1-\sin x}{\sin x}\cdot\dfrac{\sin x}{\cos x}=\dfrac{1-\sin x}{\cos x}\cdot\dfrac{1+\sin x}{1+\sin x}=\dfrac{1-\sin^2x}{\cos x(1+\sin x)}\\\\=\dfrac{\cos^2x}{\cos x(1+\sin x)}=\dfrac{\cos x}{1+\sin x} \\\\L_s=R_s[/tex]
[tex]Used:\\\csc x=\dfrac{1}{\sin x}\\\\\cot x=\dfrac{\cos x}{\sin x}\\\\\sin^2x+\cos^2x=1\to\cos^2x=1-\sin^2x\\\\(a-b)(a+b)=a^2-b^2[/tex]
