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anonymous97
 one year ago
If sin Θ = 2 over 7 and tan Θ > 0, what is the value of cos Θ?
anonymous97
 one year ago
If sin Θ = 2 over 7 and tan Θ > 0, what is the value of cos Θ?

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anonymous
 one year ago
Best ResponseYou've already chosen the best response.0so do you know SOHCAHTOA?

anonymous
 one year ago
Best ResponseYou've already chosen the best response.0so if opposite over hypotenuse is 2/7 then cos is...

anonymous
 one year ago
Best ResponseYou've already chosen the best response.0because sin and cos of one angle is the same

welshfella
 one year ago
Best ResponseYou've already chosen the best response.1one way to do it would be to use the identity cos^2 x = 1  sin^2 x

anonymous
 one year ago
Best ResponseYou've already chosen the best response.0dw:1439852492795:dw

anonymous
 one year ago
Best ResponseYou've already chosen the best response.0dw:1439852539120:dw

welshfella
 one year ago
Best ResponseYou've already chosen the best response.1No Sammy not always true

welshfella
 one year ago
Best ResponseYou've already chosen the best response.1its only true for 45 degrees

welshfella
 one year ago
Best ResponseYou've already chosen the best response.1dw:1439852609072:dw

xapproachesinfinity
 one year ago
Best ResponseYou've already chosen the best response.0it will work why not just consider you working on first quadrant since tan>0 and sin>0 so must be first quad

welshfella
 one year ago
Best ResponseYou've already chosen the best response.1another way would be to use pythagoras theorem to find the adjacent side then cos = adj / hyp

xapproachesinfinity
 one year ago
Best ResponseYou've already chosen the best response.0dw:1439852745494:dw

xapproachesinfinity
 one year ago
Best ResponseYou've already chosen the best response.0use Pythagoras to find x and then find cos theta

xapproachesinfinity
 one year ago
Best ResponseYou've already chosen the best response.0but the easiest way is the use of identity cos^2+sin^2=1 like @welshfella said

Nnesha
 one year ago
Best ResponseYou've already chosen the best response.0we can use that identity to find exact value of cos ?? aww never seen that before o.O

xapproachesinfinity
 one year ago
Best ResponseYou've already chosen the best response.0yeah why not?

xapproachesinfinity
 one year ago
Best ResponseYou've already chosen the best response.0you have sintheta =2/7 just put it into the equation and solve for cos

Nnesha
 one year ago
Best ResponseYou've already chosen the best response.0ohh got it i forgot to take square root

xapproachesinfinity
 one year ago
Best ResponseYou've already chosen the best response.0ah i see haha

xapproachesinfinity
 one year ago
Best ResponseYou've already chosen the best response.0square root produces two values you have to consider tan>0 again

anonymous97
 one year ago
Best ResponseYou've already chosen the best response.0A. 3 square root of 5 over 7 B. negative 3 square root of 5 over 7 C. 3 square root of 5 D. negative 3 square root of 5

anonymous97
 one year ago
Best ResponseYou've already chosen the best response.0those are my answer choices

welshfella
 one year ago
Best ResponseYou've already chosen the best response.1cos^2 x = 1  sin^2 x = 1  4/49 = 49/49  4/49 = 45/49 cos x = sqrt (45/49) can you finish this off?

welshfella
 one year ago
Best ResponseYou've already chosen the best response.1hint factor 45 and look for perfect squares
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