We know that
if cos x is positive
and
sin x is negative
so
the angle x belong to the IV quadrant
cos x=5/13
we know that
sin²x+cos²x=1-------> sin²x=1-cos²x------> 1-(5/13)²---> 144/169
sin x=√(144/169)-------> sin x=12/13
but remember that x is on the IV quadrant
so
sin x=-12/13
Part A) <span>cos (x/2)
cos (x/2)=(+/-)</span>√[(1+cos x)/2]
cos (x/2)=(+/-)√[(1+5/13)/2]
cos (x/2)=(+/-)√[(18/13)/2]
cos (x/2)=(+/-)√[36/13]
cos (x/2)=(+/-)6/√13-------> cos (x/2)=(+/-)6√13/13
the angle (x/2) belong to the II quadrant
so
cos (x/2)=-6√√13/13
the answer Part A) is
cos (x/2)=-6√√13/13
Part B) sin (2x)
sin (2x)=2*sin x* cos x------> 2*[-12/13]*[5/13]----> -120/169
the answer Part B) is
sin(2x)=-120/169
Answer:
The correct option is;
A. 90 degrees clockwise rotation
Step-by-step explanation:
From the given information, we have;
The coordinates of the pre-image is K(-6, 9)
The coordinates of the image is k'(9, 6) which is similar to a transformation of a pre-image of (x, y) to an image of (y, -x)
The transformation from (x, y) to (y, -x) can be obtained from either;
1) A rotation of 90° (clock wise)
2) A rotation of 270° counter clockwise
Therefore, the correct option that maps K(-6, 9) to K'(9, 6) is a 90 degrees clockwise rotation.
<h3>
Answer: 2 < x < 7</h3>
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Explanation:
We'll use the hinge theorem here. This says (more or less) that the larger an angle is, the side opposite of that will be longer.
Imagine that the segments with the single tickmarks represent a door swinging open/shut. The more open a door is, the further the distance it is from the handle to the frame. In terms of these triangles, the segment 25 is larger than 5x-10 because the angle 90 (opposite the 25) is larger than the angle 85 degrees (opposite the 5x-10)
In symbols we say
5x - 10 < 25
We also say 5x - 10 > 0 or 0 < 5x - 10 to ensure that the segment of length 5x-10 is not 0 or negative.
Put the two inequalities together and we get 0 < 5x - 10 < 25
------------
Solve for x
0 < 5x - 10 < 25
0+10 < 5x - 10 < 25 + 10 .... adding 10 to all sides
10 < 5x < 35
10/5 < 5x/5 < 35/5 ... dividing all sides by 5
2 < x < 7
We have x between 2 and 7, and not equal to either endpoint.
Answer:
45 degrees
Step-by-step explanation:
the right angle is 90 degrees and one angle is 45 degrees and 90+45=135 and 180-135=45 so 45 degrees is the missing angle
