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    in a question, the formula 4sinx +3cosx was put into the form 5sin(x+0.466). from this, how could i tell what the minimum is, and also what the smallest positive value for x for which this minimum occurs is?
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    dy/dx init
    use product rule!

    i think im tired right now so dunno if this is right good luck!
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    Well, what's the smallest value that sin(theta) can take? So what about 5 sin (theta)? And when does the sine function give it's lowest value? Solve x + 0.466 equal to that.

    jus-mi, there's no need for calculus.
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    (Original post by DominF)
    in a question, the formula 4sinx +3cosx was put into the form 5sin(x+0.466). from this, how could i tell what the minimum is, and also what the smallest positive value for x for which this minimum occurs is?
    I think the minimum would be when sin(x+0.466) = -1, so that 5sin(x+0.466) = -5. This is when x+0.466 is 3pi/2 (i think) so x can be found.
    Please can anyone else tell me if I'm right or wrong, thanks.
 
 
 
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