Let a be the fourth quadrant angle, and simplify the cosa root number 1 sina 1 sina sina root nu

cosa√（1-sina）/（1+sina）+sina√（1-cosa）/（1+cosa）

a is the fourth quadrant angle.

sina 2 + cosa 2 0, sina 2-cosa 2 0, sina 2 and cosa 2 are different names.

Original = - (cosa 2+sina 2)(cosa 2-sina 2)*(sina 2-cosa 2) (sina 2+cosa 2)-2sina 2*cosa 2*(sina 2) (cosa 2).

cosa/2-sina/2)^2-2(sina/2)^2

1-sina-(1-cosa)

sina+cosa

1-sina)/(1+sina)

1-sina)^2/(1-sina)(1+sina)(1-sina)^2/[1-(sina)^2](1-sina)^2/(cosa)^2

So the root number is under (1-sina) (1+sina)|1-sina|/|cosa|

In the same way, under the root number (1-cosa) (1+cosa)|1-cosa|/|sina|

sina<1,1-sina>0

Similarly, 1-cosa>0

a is the fourth quadrant angle.

sina<0,cosa>0

So the original formula = cosa*(1-sina) cosa+sina*(1-cosa) (-sina).

1-sina-1+cosa

cosa-sina

Since it is in the fourth quadrant, cos >0 and sin <0, and then using the denominator is fine.

How can it be so simple??

1-sina) (1+sina), 1-sina=(1-sina) 2 cavity cherry [1-(sina) 2]=(1-sina) 2 (cosa) 2 (cosa) 2 (1-cosa) (1+cosa)=(1-cosa) 2 (sina) 2 (sina) 2 because sina = 0a is the first quadrant angle containing the second quadrant |sina|=sina,|cosa|=-cosa, so the original =cosa*|1-sina|/|cosa|+sina|1-c...

Dear landlord.

First, multiply the numerator denominator in the root of the first term by 1-cosa, since the square of sina + the square of cosa = 1, so the first term is equal to (1-cosa) sina

Then multiply the numerator and denominator in the root number of the second term by 1 + cosa at the same time, since the square of sina + the square of cosa = 1, so the second term of the withered number is equal to (1 + cosa) sina

Finally, the first term is added to the second term to give 2 sina

Because a is the third symbolic call limiting angle, the sine cosine is the number of the manuscript of the negative mountain chain, cosa root number (1-sina 2) + 2sina root number (1-cosa 2).

cosa/(-cosa)+2sina/(-sina)

1+2x(-1)

a is the second quadrant angle, dissipation.

sinα＞0

Natampisina sin sin = 1- 16 25 = 3 5tan = sin cps = 3 4

(1) A is the fourth quadrant angle, then cosa>0 tana<0cosa= (1-sin a)= (1-3 4)=1 2tana=sina cosa=- 3

2) A is the second quadrant angle, then sina >0 tana<0 sina = (1-cos a) = (1-25 169) = 12 13tana = sina cosa = -12 5

3) 1/cos²a=(sian²a+cos²a)/cos²a=tan²a+1=(-3/4)²+1=25/16

cos²a=16/25

So cosa = 4 5

sina = (1-cos a) = (1-16 25) = 3 5 two cases (1) cosa = 4 5 sina = -3 5 (2) cosa = -4 5 sina = 3 5

This one.. sin is a negative number, and this angle is said to be the fourth in the question of the quadrant sin60=root3 2, then a=2k -60

2) 5, 12, 13 is the number of valleys, cos is negative, and a is in the second quadrant, so sina>0 tana<0 sina = 12 13 tana = -12 5

3) 3 4 5 is the Pythagorean number tan<0 This angle is in the 2 4 quadrant, so the positive and negative of sin and cos cannot be determined: sin=3 5, cos=-4, 5

or sin=-3 5 cos=4 5