A cutout or an embossed diagram may be used to explain this concept. Provide
squares with dotted lines on the opposite and adjacent sides. Let the child count the
total number of squares. Make a square with dotted lines for the hypotenuse too and
let the child understand that the number of squares on the hypotenuse side are equal
to the sum of squares on the opposite and adjacent sides.
- Trigonometric ratios
Consider the right angle triangle ABC, where angle B = 90o and let us consider any
one of the acute angles say angle A = theta. Then
Sine = hypotenuse^ ⎜⎛⎝ACAB⎠⎞⎟
opposite side
Cosine = hypotenuse
adjacent side
Tangent = adjacent side
opposite side
Cosecant = opposite side
hypotenuse
Secant = adjacent side
hypotenuse
Cotangent = opposite side
adjacent side
The six trigonometric ratios namely sine, cosine, tangent, cosecant, secant and
cotangent are normally written as sin, cos, tan, cosec, sec and cot respectively.
A
B C
θ
