I do not understand a thing about trigonometry, and i do no not why and how you calculate angles when you one a sin and onother a cos...
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I cannot give you a whole lecture here, but I explain the following :
Trigonometry as the name implies has to do with triangles. All sorts of triangles but the most common is the right angle triangle.
Let us look at a right angle triangle ABC where A (90 degrees) is on the left
to the right is B and above A is C
The opposite sides are usually named a, b and c where a is opposite the Angle A
b is opposite angle B and c opposite angle c
The trigonometric numbers which always refer to some angle are sinx, cosx, tanx, cotx, secx, cosecx where x is the angle
These figures you get are RATIOS (no units, since they are straight ratios) and all these numbers you see in tables or your calculator ar a ratio.
The rules tell us (for a right angle triangle) that sinx=(opposite side)/hypotenuse cosx=(adjacent side)/hypotenuse tanx=(opposite side)/(adjacent side) cotx=(adjacent side)/opposite side, secx=1/cosx= hypotenuse/adjacent cosecx=hypotenuse/opposite
IMPORTANT relations of trig. numbers sin^2x+cos^2x=1 tanx=sinx/cosx cotx=cosx/sinx
secx=i/cosx cosecx=1/sinx important also is 1+tan^2x=sec^2x
You should know some important trig numbers for these angles in degrees :
0, 30, 45, 60, 90
In order to understand better imagine a circle, centre (0,0) and radius 1 unit
The axes are the same as what they are in a graph
If on the right hand side on the x-axis is the point 0 remember that the angles increase in a counter-clockwise direction! So at point 0 angle is zero going 90 degrees up you get to 90 degrees then with a further 90 degrees 180 degrees etc
the area between 0 and 90 degrees is called the first quadrant and now it is here we look at the trig. nos.
cosines are ALWAYS the projection of the point on the circle on the x-axis and the sines on the y-axis
I could go on and on....but I hope you have some idea now as to what these trig. nos are!!
Trigonometry as the name implies has to do with triangles. All sorts of triangles but the most common is the right angle triangle.
Let us look at a right angle triangle ABC where A (90 degrees) is on the left
to the right is B and above A is C
The opposite sides are usually named a, b and c where a is opposite the Angle A
b is opposite angle B and c opposite angle c
The trigonometric numbers which always refer to some angle are sinx, cosx, tanx, cotx, secx, cosecx where x is the angle
These figures you get are RATIOS (no units, since they are straight ratios) and all these numbers you see in tables or your calculator ar a ratio.
The rules tell us (for a right angle triangle) that sinx=(opposite side)/hypotenuse cosx=(adjacent side)/hypotenuse tanx=(opposite side)/(adjacent side) cotx=(adjacent side)/opposite side, secx=1/cosx= hypotenuse/adjacent cosecx=hypotenuse/opposite
IMPORTANT relations of trig. numbers sin^2x+cos^2x=1 tanx=sinx/cosx cotx=cosx/sinx
secx=i/cosx cosecx=1/sinx important also is 1+tan^2x=sec^2x
You should know some important trig numbers for these angles in degrees :
0, 30, 45, 60, 90
In order to understand better imagine a circle, centre (0,0) and radius 1 unit
The axes are the same as what they are in a graph
If on the right hand side on the x-axis is the point 0 remember that the angles increase in a counter-clockwise direction! So at point 0 angle is zero going 90 degrees up you get to 90 degrees then with a further 90 degrees 180 degrees etc
the area between 0 and 90 degrees is called the first quadrant and now it is here we look at the trig. nos.
cosines are ALWAYS the projection of the point on the circle on the x-axis and the sines on the y-axis
I could go on and on....but I hope you have some idea now as to what these trig. nos are!!
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This is a very vague question.
It would be better if you asked a numerical question.
It would be better if you asked a numerical question.