Ratios of trigonometry
There are six types trigonometry ratios are there
- Sin∅
- Cos∅
- Tan∅
- Cot∅
- Sec∅
- Cosec∅
Sin A=
opposite of a angle
Hypotenuse
Cos A=
adjcent side
Hypotenuse
Tan A=
opposite
Adjacent
Examples::1
If tan A =3/4, then find the other trigonometry ratio of angle A.
Sol::
Given tan A=3/4
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Hence tan A=opposite side
Adjacent side
=3/4
Therefore, opposite side:adjacent side
=3:4
For angle A, opposite side=BC=3k
Adjacent side=AB=4k
Now, we have in triangle ABC
(By Pythagoras theorem)
AC²=AB²+BC²
=(3k)²+(4k)²
AC²=√25k²
AC=5k=hypotenuse
Now, we can easily write the other ratios of trigonometry
Sin A=3k/5k=3/5
Cos A=4k/5k=4/5.
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