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    can someone help me with this, i dont understand what sin(180-theta) =sintheta means also i dont understand how to express for example sin(theta) in terms of sin(theta)

    please someone help me and explain it to me
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    see what happens if you put different angles for theta in sin( 180 - theta ) and sin ( theta )
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    (Original post by the bear)
    see what happens if you put different angles for theta in sin( 180 - theta ) and sin ( theta )



    E.g if i put sin(180-46) the answer is the same as sin (46)

    but what does express in term of sin(theta) means, for example sin(-theta)
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    (Original post by Mr revision)
    E.g if i put sin(180-46) the answer is the same as sin (46)

    but what does express in term of sin(theta) means, for example sin(-theta)
    so we can say that sin( 180 - Θ ) can be written as sin ( Θ )

    we have expressed sin( 180 - Θ ) in terms of sin ( Θ )
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    (Original post by Mr revision)
    can someone help me with this, i dont understand what sin(180-theta) =sintheta means also i dont understand how to express for example sin(theta) in terms of sin(theta)

    please someone help me and explain it to me
    Draw a graph of sin\theta. Because it is periodic and symmetric (about certain values), you should be able to see why the above is true.
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    (Original post by the bear)
    so we can say that sin( 180 - Θ ) can be written as sin ( Θ )

    we have expressed sin( 180 - Θ ) in terms of sin ( Θ )


    sorry to be bothering you but how will you work out for example if the question says given that theta is an acute angle measured in degrees, express in terms of sin(theta) sin(-theta)

    please help me and thanks also this is not my homework by the way, its independent work
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    (Original post by RogerOxon)
    Draw a graph of sin\theta. Because it is periodic and symmetric (about certain values), you should be able to see why the above is true.
    From the graph, you should see:

    sin(180-\theta)=-sin(-\theta), as you're translating the \theta=0 point from where the curve goes down to where it goes up, so need to negate it.

    Then:
    -sin(-\theta)=sin\theta should be obvious from the graph.
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    (Original post by Mr revision)
    sorry to be bothering you but how will you work out for example if the question says given that theta is an acute angle measured in degrees, express in terms of sin(theta) sin(-theta)

    please help me and thanks also this is not my homework by the way, its independent work
    just look up sin 30, sin -30

    sin 56, sin -56

    you should spot a pattern ?
 
 
 
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