posted by Matt on .
I do not understand these problems. :S
I'd really appreciate the help.
Use trigonometric identities to transform the left side of the equation into the right side.
cot O sin O = cos O
sin^2 O - cos^2O = 2sin^2 O -1
(tan O + cot O)/tan O = csc^2 O
for most of these you have to know your basic trig relationships
tanx = sinx/cosx ; cotx = cosx/sinx
cscx = 1/sinx ; secx = 1/cosx
sin2x + cos2x = 1
and its re-arrangements.
so for the first :
LS = cotOsinO
Most are this easy.
last one : (I will use x as my angle)
= (sinx/cosx + cosx/ sinx)/(sinx/cosx)
= (sin2x + cos2x)/(sinxcosx) x (cosx/sinx)
try the second one, it is even easier.
solve for x to the nearest thousandth: 2tan square x-5tan x-1