What is the cotangent value of the triangular culvert number 22 5 degrees 20

By the half-angle formula:

tan( 2)= (1-cos) (1+cos)) is a positive value since * 2=45°.

Because cos45 degrees = (2

Obtained by cos(2x) = 2(cosx) 2-1.

cos45 degrees = 2 (degrees) 2-1

Solution (degrees) = ((cos45 degrees + 1) 2).

。The analysis process is as follows:

Let a = degrees, then 2a = 45 degrees.

So tan2a=1, then 2tana (1-tan a)=1, the formula: tan( +=(tan +tan ) (1-tan tan).

tan²a+2tana-1=0

Because tana=>0

SoAdditional Information:

Commonly used and angle formulas.

sin(α+=sinαcosβ+ sinβcosα

sin(α-=sinαcosβ-sinb*cosα

cos(α+=cosαcosβ-sinαsinβ

cos(α-=cosαcosβ+sinαsinβ

tan(α+=(tanα+tanβ) / (1-tanαtanβ)

tan(α-=(tanα-tanβ) / (1+tanαtanβ)

Half-angle formula. sin^2(α/2)=(1-cosα)/2

cos^2(α/2)=(1+cosα)/2

tan^2(α/2)=(1-cosα)/(1+cosα)

tan(α/2)=sinα/(1+cosα)=(1-cosα)/sinα

Commonly used special angles as function values:

1、sin30°=1/2

2、cos30°=(√3)/2

3、sin45°=(√2)/2

4、cos45°=(√2)/2

5、sin60°=(√3)/2

6、cos60°=1/2

7、sin90°=1

8、cos90°=0

9、tan30°=(√3)/3

10、tan45°=1

11. Tan90° does not exist.

The trigonometric value of the degree angle is calculated using the construction method.

Let a= degrees.

then 2a = 45 degrees.

So tan2a=1

Then 2tana (1-tan a) = 1

tan²a+2tana-1=0

Because tana=>0.

Let a= degrees.

then 2a = 45 degrees.

The split is blinded by tan2a=1

Then 2tana (1-tan a) = 1

tan²a+2tana-1=0

Because the disadvantage ruler tana = >0

So the rental source is high.

tan45 = root number 2-1

The commonly used sum angle formula sin( +sin cos + sin cos sin( -sin cos -sinb*cos cos( +cos cos -sin sin cos( -cos cos +sin tan( +tan +tan ) 1-tan tan )tan( -tan -tan ) 1+tan tan ) half-angle formula sin 2( 2) = (1-cos ) 2cos 2( 2) = (1+cos ) 2tan 2( 2)=(1-cos) 1+cos )tan( 2)=sin (1+cos )=1-cos ) sin Commonly used Huizi special angle function value: 1, sin30°=1 22, cos30°=(3) 23, sin45°=(2) 24, cos45°=(zhi晌2) 25, sin60°=(3) 26, take Bifeng cos60°=1 27, sin90°=18, cos90°=09, tan30°=( 3) 310, tan45°=111, tan90° do not exist.

Answer: That's all it takes. Exams don't have to be that complicated.