1. By Nittaya Noinan Kanchanapisekwittayalai phetchabun school Grade 10 Trigonometry
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6. Trigonometry ( 三角幾何 ) means “Triangle” and “Measurement” Introduction Trigonometric Ratios In F.2 we concentrated on right angle triangles .
7. Unit Circle A Unit Circle Is a Circle With Radius Equals to 1 Unit.(We Always Choose Origin As Its centre) 1 units x Y
8. Trigonometry Trigonometry is the branch of mathematics that looks at the relationship between the length of the sides and the angles in a right angled triangle. It helps us calculate the length of unknown sides, without drawing the triangle, and it also helps us calculate the size of an unknown angle without having to measure it. Let us look at a right angle triangle.
9. Trigonometry O F C Hypotenuse x 0 Opposite Adjacent O F C Hypotenuse y 0 Opposite Adjacent The ‘Hypotenuse’ is always opposite the right angle The ‘Opposite’ is always opposite the angle under investigation. The ‘Adjacent’ is always alongside the angle under investigation.
10. Trigonometry 6 3 O F C Let us look at the ratio or fraction of the opposite over the adjacent. Let us now split this triangle up. 27 0
11. Trigonometry 4 2 2 3 O E F B C Let us look at the ratio or fraction of the opposite over the adjacent Let us split it again. 27 0