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1.When a=0, it is a one-dimensional equation, and x=-1 2 satisfies the requirements of the problem.
2.When a is not 0, it is a quadratic equation and must have a real root.
x1 + x2 = -2/a
x1*x2 =1/a
b^2-4ac = 4-4a>=0
Solution: a<=1, and a is not 0
1) If x1 and x2 are both negative, then x1 + x2 = -2 a < 0 and x1*x2 =1 a >0 solve: 0 then x1*x2 =1 a <0 solves: a<0 In summary, a<= 1, the problem requirements are satisfied.
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Because there must be a solid root, then a≠0 when 4 4a 0, a 1, the intersection of the image and the x-axis is 1,0 , which is true.
When 4 4a 0, a 1, when 1 a 0, the abscissa of the intersection point to the left of the intersection point with the x-axis is b δ 2a, according to the title, b δ 2a 0, 2a 0, b δ 0, δ0, b δ, holds.
When a 0, the abscissa of the intersection point to the left of the intersection point of the x-axis is b δ 2a, and according to the title, b δ 2a 0, 2a 0, b δ 0, δ0, δb, holds.
When 4 4a 0 and a 1, the graph and the coordinate axis have no intersection point.
In summary, 0 a 1 or a 0
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Sub-situation: 1When a=0, it is a one-dimensional equation, and x=-1 2 satisfies the requirements of the problem.
2.When a is not 0, it is a quadratic equation and must have a real root.
x1 + x2 = -2/a
x1*x2 =1/a
b^2-4ac = 4-4a>=0
Solution: a<=1, and a is not 0
1) If x1 and x2 are both negative, then x1 + x2 = -2 a < 0 and x1*x2 =1 a >0 solve: 0 In summary, a<= 1, the problem requirements are satisfied.
So, obviously, this answer of yours is wrong, dear
If you still have doubts, please feel free to ask and ask.
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Solve using Vedder's theorem and discriminants.
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Because sin2a = sin2b angle a is either equal to angle b or equal to (180 degrees - angle 2a) e.g. sin30 degrees = sin150 degrees.
Assuming that angle a is equal to angle b, this situation does not exist. Because there is already 0 above that is less than a and less than b than 180 degrees, it is assumed that it does not exist.
So angle 2b can only be equal to (180 degrees - angle 2a).
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I think the answer is very detailed, is there any problem?
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a-b=(sinx-cosx,o)
A times (a-b) = (sinx-cosx, 0) times (sinx, cosx) oak shed = sinx 2-sinxcosx = 1-cosx 2-1 and manuscript 2sin2x
1 2-1 2 (sin2x + cos2x) = 1 2 - 2 times the root number of the second half of the sin (2x + the party of the four beams).
Therefore, the minimum positive period is pie.
2sinxcosx=sin2x
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(1) Derived from the original formula.
f(x)=-√3sin²x+
√3/2)*cos2x+(1/2)*sin2x-√3/2=sin(2x+π/3)-√3/2
Substituting x=25 6 gives the value as sin(2 3+8 )-3 2=0
2) f(a 2) = sin(a + 3) - 3 2 = 1 4- 3 2, a (0, ) then sin(a + 3) = 1 4<1 2, cos(a + 3) = - 15 4, then sina = sin(a + 3 - 3) = sin(a + 3) * (1 2) - cos(a + 3) * (3 2).
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f(x)=(-√3/2)(1-cos2x)+1/2sin2x=(√3/2cos2x+1/2sin2x)-√3/2=sin(2x+π/3)-√3/2
The first question is f(25 6) = f( 6) = sin(2 3) - 3 2 = 0
The second question is f(a 2) = sin(a + 3) - 3 2 = 1 4- 3 2 sin (a + 3) = 1 4
1/2sina+√3/2cosa=1/4
There is sin 2a + cos 2a = 1
So sina = (1 + 3 5) 8
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(1)f(x)=-√3sin²x+
3 2*cos2x+1 2*sin2x- 3 2=sin(2x+ 3)- 3 2 (1) so f(25 6)=sin(26 3)- 3 2=sin(2 3)- 3 2=0
2) Because f(a 2) = 1 4- (3) 2 is substituted for (1), sin(a+ 3) = 1 4
Thus sina * cos 3 + cosa*sin 3 = 1 4 and because sina 2 + cosa 2 = 1 from a (0, ) finally get sina = (1 + 3 5) 8
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Let t=sinx, x [0, 2].
t∈[0,1]
The function becomes: y=t +t 2
y=t +t2 increases monotonically on [0,1], and ymin=0 when t=0
t=1, ymax=3 2
The value range is [0,3 2].
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