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y= sin(π/6-2x)-cos2x
sin2xcosπ/6+cos2xsinπ/6)-sin(2x+π/6)
Minimum positive period: 2 2 =
When 2x+6=2k-2, the maximum ymax=1 at this time x = k-3, where x belongs to z
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We haven't learned trigonometry yet, and we'll learn it in a week.
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First of all, it should be satisfied that the formula under the root number should be greater than 0, that is, 1+2cos2a 0 1-2cos2a 0 to get a belongs to [ 6, 3] or [2 3, 5 6] or [7 6, 4 3] or [5 3, 11 6].
Secondly, the inequality is squared at the same time, so that 4sin a 2-2 (1-4cos a) 4, 4sin a 2-2 (1-4cos a) can be deduced to obtain (1-4cos a) cos 2a deduced (cos2a-1) 0 constantly.
2-2 (1-4cos a) 4 can be deduced (1-4cos a) -2 constantly.
In summary, the result should be that a belongs to [6, 3] or [2 3, 5 6] or [7 6, 4 3] or [5 3, 11 6].
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The part of the absolute value is squared to get 2-2*under the root sign (1-4*cos2a 2), and then the term is shifted and simplified to prove the new inequality: 2*sina 2<=1-under the root sign (1-4*cos2a 2)<=2. To the left of the proband, 1-2*sina 2=cos2a.
After the two sides are shifted, 1-4*cos2a 2<=cos2a 2, so cos2a>=1 5The right one is obviously true, because [under the root number (1+2cos2a)]<2....Did you make a mistake???
It's all like this...
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For af bc, then de is better than af=cd than ac=1 to 3, so. af=3de
and ab=4de
So sinb = 3de is better than 4de = 3 to 4
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1. sin -cos = 1 2 square on both sides to get sin *cos = 3 8, sin +cos = 1 + 2 * 3 8 = 7 2
2. Because sin -cos = 1 2, sin +cos = 7 2, so sin = (1+ 7) 4, cos = (1 + 7) 4, tan = sin cos = (4 + 7) 3
sin4 to the power -cos4 +tan = (sin2 to the power + cos2 ) * sin2 to the power -cos2 ) + tan
sinθ+cosθ)*sinθ-cosθ)+tanθ=7/12*√7+4/3
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1: The note f(x)=sin2x+acos2x is symmetrical from the image of y=sin2x+acos2x with respect to the straight line x=8:
f(-4)=f(0), i.e.: -1=a
2: To correct the problem, the definition domain of f(x) should be negative infinity to zero and zero to positive infinity, otherwise f(0)=0, and f(1 2)=0 from the properties of the odd function, so f(x) in (- not monotonic contradicts the title.
Solution: From the properties of the odd function: f(1 2) = f(-1 2) = 0, and f(x) also increases monotonically at (- 0).
Obtained from the images of f(cosa) 0 and f(x).
cosa -1 2 or 0 cosa 1 2 again because a is the inner angle of a triangle.
So a can be in the range of (0, 3) or (2 3), your answer is incorrect.
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Regarding the origin symmetry, it is an odd function, and cosx is not an odd function, sinx is an odd function, and cos(x+ 2+k)=sinx, so we want to express the following cos in the form of 2+k, so the same as below.
Using sina + sinb = 2 sin((a+b) 2)cos((a-b) 2
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Right triangle definition.
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