Trigonometry. Poem by Nash Thomas

You may be bored in the maths classes,
You may be bored due to trigonometry,
You need to know the same,
If you want to follow astronomical studies,
You can learn all formulae by some tricks,
Tricks to memorize all the boring formulas,
Try to memorize ‘PH-BH’
Need to know P as perpendicular,
Need to know B as base,
Need to know H as the hypotenuse,
Try to memorize Sine, Cos and Tan,
Sine, Cos, Tan as a sequence,
Put a slash before H,
P/H gives sine,
B/H gives Cos,
Ignoring all H,
P/B gives Tan
Try to memorize one thing,
Cosec, Sec and Cot as sequence,
The reciprocal of sine, cos and tan gives-
Cosec, Sec and Cot.
H/P gives Cosec,
H/B gives Sec,
B/P gives cot.
Read it loudly for seven times,
You will learn it quickly.