I don't have a calculator. It's urgent

RELATED INFORMATIONS

• 1. How much is sin65 °× cos20 ° - sin65 °× sin20?
• 2. Do you know how much sin65 ° * cos20 ° - sin65 ° * sin20 ° is equal to
• 3. Sin65 * cos20-sin65 * sin20 please note that the latter two are sin. I need a process. Thank you
• 4. What is sin130 ° and sin11.7 ° equal
• 5. How much is 100 degrees centigrade
• 6. What is the value of sin20 · sin30 + cos30 · cos20? 20,30 are degrees
• 7. The solving process of cos20 / 2cos10 ° minus sin20%
• 8. Vertical relationship If PA ⊥ BC, Pb ⊥ AC, then the projection of point P on plane ABC is ⊥ ABC_____ 2. P is a point outside the plane where △ ABC is located. If PA = Pb = PC, then the projection of P on the bottom surface is____ 3. Given that three line segments intersect at the same point P, the line segments PA, Pb and PC are perpendicular, and a, B and C are in the same plane, P is outside the plane ABC, and pH is perpendicular to the plane ABC at h, then the perpendicular foot h is △ ABC____ (inner / central / perpendicular / outer) 4. In the cube abcd-a1b1c1d1, e and F are the midpoint of edge Aa1 and CC1, respectively Please use the three perpendicular theorem to solve the fourth question in detail
• 9. It's depressing that I didn't bring the book with me Not too much. It's better to write down one point at the end of each summary on no more than one piece of paper Three lines per chapter... No books on holiday
• 10. Exercise 3.3 on page 110, the first question of the last question in group B I have worked out is (4), the title is that the vertex a (5,1) of △ ABC is known, the equation of the line where the central line cm on the edge of AB is 2x-y-5 = 0, and the equation of the line where the high BH on the edge of AC is x-2y-5 = 0 (1) The coordinates of vertex C; (2) The equation of the straight line BC
• 11. Who's bigger, sin 15 or sin 20
• 12. The mercury surface of the thermometer is at 38 degrees centigrade. A student uses the same thermometer to measure the questions of a, B and C. The results show that a is 38 degrees centigrade, B is 38.5 degrees centigrade and C is 39 degrees centigrade A. A's temperature must be abnormal B. B's questions must be abnormal C. three students' questions must be abnormal d. A's questions must be normal Explain the process of thinking
• 13. The temperature range is between 38.9 ℃ and 41.1 ℃, expressed as a ± B
• 14. -9 degrees centigrade Hurry
• 15. In the form of a ± B, the growth rate is between 35% and 36%, and the temperature is between - 38.9 ° and - 41.1 ℃
• 16. What is Tan 40 ° - cot 40 degrees
• 17. Tan20 degree + tan40 degree + root 3 tan20 degree, tan40 degree =?
• 18. What's the difference between 4sin40 and tan40? Please write down the detailed process In the middle is the minus sign
• 19. 4cos50°-tan40°=______ ．
• 20. What is 40 degrees