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trig limit ques (1 Viewer)

Calculon

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When you have a limit with sinqx/sinzx and x-->0 it ends up being q/z. The answer to this one is 4*3/2=6

if in doubt substitute in 0.00001, not very methodical but it works.
 

jimmik

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Originally posted by Calculon
When you have a limit with sinqx/sinzx and x-->0 it ends up being q/z. The answer to this one is 4*3/2=6
in an exam can u jus put that as the answer, or jus state since lim x-> 0 for sinqx/sinzx = q/z? dont u need workin out?
 

ND

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lim 4sin3x/sin2x
=4*lim (sin3x/3x)*(3x/sin2x)
=4*lim (sin3x/3x)*lim (3x/sin2x)
=4*3/2*lim 2x/sin2x
=4*3/2=6



Originally posted by Calculon
When you have a limit with sinqx/sinzx and x-->0 it ends up being q/z. The answer to this one is 4*3/2=6

if in doubt substitute in 0.00001, not very methodical but it works.
I don't think you'd be allowed to assume that.
 

CM_Tutor

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I agree that these sorts of techniques are useful checks (but not explanations / 'proofs'), but be a bit more careful with using the 'large' values, like 1000, for infinity.
 

MML

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use L'Hopitals Rule; hehehehehe...go learn it, then u can do those q's in seconds. and out smart ur avg highsko teacher
 

Li0n

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anyone here know of a text book that has questions for that? i got cambridge year 11 thats about it, every other maths text book has no topic called "fundamental limits" as cambridge calls it i think.
 

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