cos(x) = -1/3
|sin(x)| = √(1-(1/3)²) = √(8/9) = 2√2/3
x is in the third quadrant: sin(x) must be negative.
sin(x) = -2√2/3
cot(x) = 1/tan(x)
tan(x)cot(x) + csc(x)
= tan(x)/tan(x) + 1/sin(x)
= 1 + (-3/2√2)
= 1 - 3√2/4
= (4-3√2)/4
2007-12-31 11:59:33
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answer #1
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answered by gudspeling 7
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cos x=-1/3
as cos x = adjacent side/ hypotenuse=1/3
so the opppsite side is =sqrt[(3)^2-(1)^2]=sqrt[9-1]=sqrt[8]
so tan x= opposite side/adjacent side =[sqrt(8)/1]
cot x=1/tan x=1/[sqrt(8)/1]=1/sqrt(8)
csc x= hypotenuse/opposite side = -3/sqrt(8)
so
tan x cot x + csc x
substitute the values
[sqrt(8)*1/sqrt(8)] +[ -3/sqrt(8)]
[(sqrt(8) -3)/sqrt(8)] or[1-(3/sqrt(8))]
2007-12-31 16:32:43
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answer #2
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answered by Siva 5
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cosx = - 1 / 3 , third quadrant , x= -1 , r = 3
we have , x ^ 2 + y ^2 = r ^2
y ^2 = r ^2 - x ^2 = ( 3) ^2 - ( - 1) ^2 = 8
y = 2 square root(2) , and , y = - 2 [square root(2)]
in third quadrant , y < 0 , we get y = - 2[ square root (2)]
sinx = y / r = - [ 2square root( 2)] / 3
cscx = 1 / sinx = - 1 /{ [ 2 square root (2)] / 3}
cscx = - 3 / [ 2 square root (2)] =
= - [(3)( square root(2))] / 2 [(square root (2)] ^2
cscx = - [ 3 square root (2) ] / 4
we have ,tanx = 1 / cotx
so
tanx cotx + cscx = (1/ cotx) cotx + cscx = 1 + cscx
tanx cotx + cscx = 1 - {[ 3 square root (2)] / 4 }
2007-12-31 12:46:07
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answer #3
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answered by LE THANH TAM 5
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tanx cotx + csc x = 1 - 3/(2*2^0.5)
2007-12-31 12:24:06
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answer #4
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answered by imamulleith 2
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If cos x = -1/3 and x is in the 3rd quadrant, you can easily work out the 3rd side of the triangle using Pythagoras. It is the opposite side, and it is equal to -2√2
So tan x would be -2√2/-1 = 2√2
cot x = 1/ tan x = 1/2√2
Csc x = -3/2√2
Remember that the radius is always positive, the line extending up is positive, down is negative, right is positive and left is negative.
I'll leave the adding and multiplying to you.
2007-12-31 12:14:57
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answer #5
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answered by Joe L 5
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k
2007-12-31 11:57:14
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answer #6
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answered by mvp14455 2
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tan x cot x + cosec x
1 + 1 / sin x
1 + 1 / (- √8 / 3)
1 - 3/√8
(√8 - 3) / √8
(2√2 - 3) / (2√2)
2007-12-31 22:26:21
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answer #7
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answered by Como 7
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Numerator = sin(x) +tan(x) = sin(x){a million+a million/cos(x)} =sin(x){cos(x) +a million}/cos(x) Denominatoe= sec(x) -cos(x) = a million/cos(x) - cos(x) ={a million-cos^2(x)}/cosx=sin^2(x)/cos(x) Divide N and Denominator cos(x) and sin(x) will cancel LS ={a million+cos(x)/sin(x) = cosec(x) + cot(x) =RS
2016-11-27 01:57:21
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answer #8
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answered by Anonymous
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