It is known that the maximum value of y = asinx + B (a < 0) is 6 and the minimum value is - 2 If SiNx = 3 / 5 and X ∈ [(a π / 3) + BX] =_ The second question is to revise it. X ∈ (π / 2, π), find the value of sin [(a π / 3) + BX]. okay.

It is known that the maximum value of y = asinx + B (a < 0) is 6 and the minimum value is - 2 If SiNx = 3 / 5 and X ∈ [(a π / 3) + BX] =_ The second question is to revise it. X ∈ (π / 2, π), find the value of sin [(a π / 3) + BX]. okay.

The maximum value of SiNx is 1 and the minimum value is - 1
So when SiNx = - 1, there is a maximum of - A + B = 6
When SiNx = 1, there is a minimum value a + B = - 2
The solution is a = - 4, B = 2
Second, the description of the X attribution interval is not clear, right?

Find the maximum and minimum of function y = asinx-2 (a > 0)

Maximum A-2,
Minimum - A-2

Finding the minimum value of F (x) with known function f (x) = cos2x - (cosx-1) cosx

Let cosx = t ∈ [- 1,1]
y=2t²-1-(t-1)t
=t²+t-1
=(t+1/2)²-5/4
So when t = - 1 / 2, there is a minimum value of - 5 / 4