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Find all the values of x in the range 0° ≤ x ≤ 180° satisfying 4tan(x) + 7sin(x) = 0 Watch

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    Hello everyone. I can't figure out how to solve the following:

    Find all the values of x in the range 0° ≤ x ≤ 180° satisfying

    4tan(x) + 7sin(x) = 0


    Thanks for the help!
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    (Original post by Callanb)
    Hello everyone. I can't figure out how to solve the following:

    Find all the values of x in the range 0° ≤ x ≤ 180° satisfying

    4tan(x) + 7sin(x) = 0


    Thanks for the help!
    You could write tanx = sins/cosx and factorize.
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    (Original post by RichE)
    You could write tanx = sins/cosx and factorize.
    thanks for the reply riche, i understood that i should use that identity but I am completely stuck on how to actually make anything useful of it.
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    (Original post by Callanb)
    thanks for the reply riche, i understood that i should use that identity but I am completely stuck on how to actually make anything useful of it.
    Like I said, factorize. Both expressions now have a sinx in them.
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    (Original post by Callanb)
    thanks for the reply riche, i understood that i should use that identity but I am completely stuck on how to actually make anything useful of it.
    u will have a sinx/cosx -7sinx.. then u can multiply it with cosx..
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    Solve further
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    (Original post by Mo3yman)
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    Solve further
    You can't cancel all the sinx. You have to take the sinx out as it is common for both. So you get
    Sinx(7cosX + 4)=0
    SinX=0. CosX=-4/7
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    (Original post by Ackashh05012911)
    You can't cancel all the sinx. You have to take the sinx out as it is common for both. So you get
    Sinx(7cosX + 4)=0
    SinX=0. CosX=-4/7
    exactly
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    (Original post by Ackashh05012911)
    You can't cancel all the sinx. You have to take the sinx out as it is common for both. So you get
    Sinx(7cosX + 4)=0
    SinX=0. CosX=-4/7
    If there is ever one rule that I have learned:
    Never cancel, just factor it out.
    You more than likely lose a solution through division or cancellation if it isn't necessary.
 
 
 
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