cosecA + cotA + cosecA-cotA = 3+1/3 = 4/3
2cosecA = 4/3
cosecA=2/3
sinA=3/2 funny
Given cosec A + cot A = 3
and thus evalute cosec A -cot A
and find cos A
]]>another way to show x=0 is a sol'n was already given by wcy in that soln; the sin x = 0 half of the soln...
]]>sin x=2 cos x
tan x=2
x=...
Are you sure we can divide sin x by cos x?
what if cos x = 0 ...
then, the answer will be undefined!
2 sinx cosx +cos^2x=cos^2x +sin^2 x
2 sinx cosx=sin^2 x
sin^2 x-2 sinx cos x=0
sin x(sin x-2 cos x)=0
sin x=0 or sin x=2 cos x
x=0,etc..
or tan x=2
x=...
2sinx.cosx + cos^2x = 1
]]>Making another right-angled triangle out of CD and the corner, we now know the side length and we want to know the hypotenuse. cosθ=a/h, so cos 60=0.1503.../h, so h=0.1503.../cos 60=0.30m to the nearest cm, which is length CD.
The outer frame has two lengths and two widths on it, so in total it is 10+10+0.8+0.8=21.6m long and one length AB is 0.8/sin 60=0.9238...m, so 21 of them are 19.40m to the nearest cm.
]]>Please help mefind the length (in millimetres) of piece CD as i already know how to find the length of AB.
After that i need to find the total length of the out frame and all 21 pieces of AB.
Any help is greatly appreciated.
Note: the vertical lines (apart from those on the outer frame) are not a part of the actual structure. They are merely usaed to form triangles so certain lengths can be calculated.
thanks.
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