In the investigative activity below, your task is to record down the trigonometric ratios ie. the sine, cosine and tangent of [math]\angle DAX[/math].[br][br]Set [math]\angle DAX=30^o,45^o[/math]or [math]60^o[/math][br]For each angle, modify the size of the triangle such that [math]AD[/math] is 10, 20 or 30 units respectively.
[size=150]When the angle is fixed at [math]30^o,45^o[/math]or [math]60^o[/math] , and the length of [i]AD [/i]is set to 10, 20 and 30 units for each angle, what do you notice about the sine, cosine and tangent ratios of [math]\angle DAX[/math]?[/size]
[size=150]For each angle, changing the size of the triangle does not change the trigonometric ratios.[/size]
[size=150]What is the key concept behind the observation in previous question? [/size]
[size=150]Although the triangles are of different sizes, they are similar triangles as the corresponding angles are equal.[br][/size][size=150]Hence the ratio of sides remain unchanged.[/size]