A round piece of paper, folded twice, can fold a few corners at most

RELATED INFORMATIONS

• 1. Fold a piece of circular paper in half three times as follows. What is the angle?
• 2. An acute trigonometric function Sin square a - (radical 3 + 1 divided by 2) Sina + radical 3 divided by 4 = 0 Find a
• 3. First simplify, then evaluate: (sin a-cos a) / (sin a + cos a), where Tan a = 2 I just don't know how to simplify. I'm preparing
• 4. 2-channel acute angle trigonometric function calculation, 4cos^2a-2(1+√3)cosa+√3=0 2cos^2a+3√3sina-5=0 Find the acute angle a satisfying the following conditions
• 5. On the calculation of acute angle trigonometric function |Tan 45 ° - Tan 60 °| + under root sign (Sin & # 178; 60 ° - 2cos 30 ° + 1)
• 6. After executing the statement "x = (a = 3, B = a --", what are the values of X, a and B in turn? How to calculate them?
• 7. As shown in the figure, the cross section of a reservoir dam is an isosceles trapezoid with a crest width of 6 meters and a dam height of 10 meters. The slope of slope AB is 1:2 (AR: BR). Now, if the crest width and slope gradient are unchanged, how much earthwork is needed to reinforce a 50 meter long dam
• 8. Can acute trigonometric function only be used in right triangle
• 9. Who can help me sum up some knowledge about right triangle
• 10. 3tan30 radical 1-2tan60 + tan2 power 60 ° + tan45 times cos45
• 11. Fold a round paper in half three times and unfold it to get the angle of () A. 30°B. 45°C. 60°D. 90°      E、180°
• 12. How to make 45 ° and 135 ° angle with round paper
• 13. As shown in the figure, in the circle O with radius one, if the angle AOB is 45 degrees, then sinc is  
• 14. As shown in the figure, it is known that △ ABC is inscribed in ⊙ o, ∠ C = 45 ° and ab = 4, then the radius of ⊙ o is___ ．
• 15. Can you make 45 degree and 135 degree angles with round pieces of paper
• 16. On the solution of sharp angle trigonometric function~ 1. In RT triangle ABC, if angle c = 90 degrees, a + C = 4, cos = 3 / 5, then a =, B =, C = area of triangle ABC? 2. There are two boats on the sea. Boat a is due south of boat B. boat a sails 60 degrees north by east at the speed of 8 knots. Boat B sails 5 knots due east, 3. In RT triangle ABC, angle c = 90 degrees, D is a point on the edge of BC, De is perpendicular to point E, angle ADC = 45 degrees, if de ratio AE = 1:5, be = 3, calculate the area of triangle abd 4. In order to alleviate the parking problem, an underground garage is planned to be built in a certain unit, and the architectural designer has provided the design schematic diagram of the underground garage. According to the regulations, the height limit sign should be posted above the broken road of underground parking, so as to inform the parking people whether the vehicle can be safely used (AB = 9 meters, BC = 0.5 meters) to indicate the height limit, please calculate according to the figure (the figure can't be uploaded, please draw it yourself)
• 17. The slope is equal to () A sine B tangent C cosine D reciprocal of tangent
• 18. Given the line y = 3x, find the sine value of the angle (acute angle) between the line and X axis
• 19. Acute trigonometric function 1. Simplification: | sin40 ° - 1 | + √ (1-cos ^ 240 °) 2. Assume 0 degree
• 20. Calculation of trigonometric function of acute angle In this lesson, I didn't come. The teacher left my homework. I'll go to class later. 1. Calculate the sine, cosine and tangent of the two acute angles in the following right triangle. 2. In RT △ ABC, if the length of each side is doubled, what's the change of the sine, cosine and tangent of the acute angle a? 3. As shown in the figure, in RT △ ABC, angle c = 90 °, AC = 8, Tana = 3 / 4, calculate the value of sina and CoSb If I can't send the pictures of question 1 and question 3, just answer the answers of question 2