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
The total length of the wire needed to make this shape is 162cm
<h3>Perimeter of a triangle</h3>
The perimeter of a triangle is the sum of the external side of the triangle.
Given the following parameters
Length of one side of the outside shape = 24cm
The side length of the smaller triangle = 24/4 = 6cm
The perimeter of the smallest triangle 3(6) = 18cm
The perimeter of the smaller triangle (at the middle) = 12(3) = 36cm
Total length of wire needed. = 3(24) + 3(18) + 36
Total length of wire needed = 72 + 54 + 36
Total length of wire needed = 162cm
Hence the total length of the wire needed to make this shape is 162cm
Learn more on perimeter of triangle here: brainly.com/question/24382052
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1/10*(f-220) or 0.1(f-220)
Answer:
Step-by-step explanation:
There were 9 other people there. First you would subtract how much marcus paid from the total (134.03-20.45=113.58). After that you just divide the remaining cost with 12.62 (113.58/12.62=9)