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    If tan theta = 1 and theta is acute, find the exact values of:
    sin theta/cos theta.

    I understand that I need to make a right angled triangle with opp =1/adj = 1 and hyp = root 2. But what does the question imply by stating that the angle is acute? If another question says the angle is obtuse what does it mean? I know that theta would be in the range 0 < x < 90 and 90 < x < 180.

    Has it got to do with which angle to use when drawing the triangle?
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    tan(45)=1
    tan(225)=1

    Which one do you want?
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    (Original post by BabyMaths)
    tan(45)=1
    tan(225)=1

    Which one do you want?
    ohh haha, i was overthinking this. cheers

    If sin theta is 5/13, and theta is obtuse, find the exact values of cos theta/tan theta.

    I got theta = 22.6 and the other value is 157.4 . But how can I make a right angled triangle with an angle of 157.4?
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    (Original post by UKBrah)
    ohh haha, i was overthinking this. cheers

    If sin theta is 5/13, and theta is obtuse, find the exact values of cos theta/tan theta.

    I got theta = 22.6 and the other value is 157.4 . But how can I make a right angled triangle with an angle of 157.4?
    The first diagram here might help.
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    together with this

    Name:  c2 trig.png
Views: 211
Size:  11.2 KB
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    (Original post by BabyMaths)
    together with this

    Name:  c2 trig.png
Views: 211
Size:  11.2 KB
    I get cos x = 12/13 and tan x = 5/12.
    The answers are negative tho, is this because both x co-ordinates are negative in the quadrant in which the triangle is in?
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    (Original post by UKBrah)
    I get cos x = 12/13 and tan x = 5/12.
    The answers are negative tho, is this because both x co-ordinates are negative in the quadrant in which the triangle is in?
    You should have -12 rather than 12 in the diagram and then you have

    tan (157.38..)= 5/-12= - 5/12

    and

    cos(157.38..)= -12/13.

    or if I actually read your question..yes that's right.
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    (Original post by BabyMaths)
    You should have -12 rather than 12 in the diagram negative and then you have

    tan (157.38..)= 5/-12= - 5/12

    and

    cos(157.38..)= -12/13.

    or if I actually read your question..yes that's right.
    how can distance be negative? :confused:
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    (Original post by UKBrah)
    how can distance be negative? :confused:
    distance isn't but direction can be
 
 
 
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