Without using trigonometric tables, prove that:

$\sin 53°\cos 37°+\cos 53°\sin 37°=1$

Without using trigonometric tables, prove that:

Without using trigonometric tables, prove that:

$\sec 70°\sin 20°+\cos 20°\mathrm{cosec}70°=2$

Without using trigonometric tables, prove that:

Without using trigonometric tables, prove that:

Without using trigonometric tables, prove that:

Prove that:

$\frac{\sin 70°}{\cos 20°}+\frac{\mathrm{cosec}20°}{\sec 70°}-2\cos 70°\mathrm{cosec}20°=0$

Prove that:

$\frac{\cos 80°}{\sin 10°}+\cos 59°\mathrm{cosec}31°=2$

Prove that:

$\frac{2\sin 68°}{\cos 22°}-\frac{2\cot 15°}{5\tan 75°}-\frac{3\tan 45°\tan 20°\tan 40°\tan 50°\tan 70°}{5}=1$