Let f (x) = 1-1 / 2cos (2x) + asin (x / 2) * cos (x / 2) (a ∈ R) have the maximum value of 3

f(x)=1-1/2cos(2x)+asin(x/2)*cos(x/2)
f(x)=(sinx)^2+(a/2)*sinx+1/2
sinx∈[-1,1]
The axis of symmetry is - A / 4
（1） -a/4>0
a

RELATED INFORMATIONS

1. In a division formula, the quotient is 6 times the divisor, and the divisor is 6 times the remainder. When the sum of quotient, divisor and remainder is 430, what is the divisor? Using equation
2. The general solution of the differential equation XY '+ y-e to the power x = 0 is y=
3. The results are as follows: (1), 3.2 * (- 7 / 8) * (- 1.25) * (1 / 7) (2) (7 / 99 / 15) * 30 (3), (- 69 / 15) * 8 Using a simple method to calculate: (1), 3.2 * (- 7 / 8) * (- 1.25) * (1 and 1 / 7) (2) (99 and 7 / 15) * 30 (just two, not the third)
4. Solve the equation: ① x2-2x-8 = 0 (by formula method) & nbsp; & nbsp; ② 2x2-4x + 1 = 0 (matching method) ③ (x + 1) (x + 3) = 15 & nbsp; & nbsp; & nbsp; & nbsp; & nbsp; & nbsp; & nbsp; & nbsp; & nbsp; & nbsp; & nbsp; & nbsp; & nbsp; ④ (Y-3) 2 + 3 (Y-3) + 2 = 0
5. 1/3+1/15+1/35+1/63+/1+1/99=?
6. Solving cubic equation x ^ 3-3x ^ 2 + 2 with one variable
7. 15/4+()=()÷9/8=()*24=1 From the bottom
8. Calculation. (1) 2xy-1 / 2x ^ 3 + 2XY + 0.5x ^ 3 + 1 / 2 (2) 3x + (- 5x ^ 3) - (- 2x) - 5x - (+ 3x ^ 2)
9. Simple calculation of 49 × 49 + 49
10. If the solution of the inequality system X ＞ 2m + 1 x ＞ m + 2 is x ＞ - 1, then the value of M is () A. - 1B. - 3C. - 1 or - 3D. - 1 < m < 1
11. How much is 1 / 4 times 2 / 3?
12. The third power of a * B minus the third power of a * B
13. How many square decimeters is 15 square centimeters equal to
14. How to read SGN in piecewise function y = sgnx? If you read it out, what's the pronunciation like? For example, what does SGN read?
15. Come on. OK, there's more money!
16. (1) -(2m-3) (2) n-3(4-2m) (3) 16a-8(3b+4c) (4) t+2/3(12-9v) (5)-(5m+n)-7(a-3b) (6)-1/2(X+Y)+1/4(p+q) (7)-8(3a-2ab+4) (8)4(m+p)-7(n-2q) ----------------------------------------------------------- Please write down the process If you are good at these people, Please tell me how to do these questions If it's good It's all well written, But please make up the process
17. First volume of junior high school mathematics to remove brackets and add brackets 1. Given that the square of M minus Mn = 20, the square of Mn minus n = minus 12, find the value of the algebraic formula m minus N and M minus 2Mn + n 2. The circumference of the triangle is 48, the length of the first side is 4A + 3b, the first side of the second side is less than 2a-b, find the length of the third side
18. To add brackets to polynomial A-B + C-D, the following addition method is wrong A、(a-b)+(c-d) B、(a+c)-(b+d) C、(a-d)+(b-c) D、 a-(b-c+d)
19. Fill in the blanks of mathematics in grade one of junior high school 1. Fill in the basis of deformation in brackets: (a + b) + C = a + (B + C) () = (B + C) + a() Mathematics choice in grade one of junior high school 1. If M is a rational number, then the result of M + | m | must be(). (A) Positive number (B) Negative number (C) Non positive number (D) Nonnegative number
20. (a-b) - (- C-D) =? This question is about removing brackets