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40
Prove that sin u/ sin v lies between u/v and pi/2 times u/v
Prove that sin u/ sin v lies between u/v and pi/2 times u/v
Source:
December 6, 2010
inequalities
trigonometry
function
calculus
inequalities unsolved
Problem Statement
Prove the inequalities
u
v
≤
sin
u
sin
v
≤
π
2
×
u
v
,
for
0
≤
u
<
v
≤
π
2
\frac{u}{v}\le \frac{\sin u}{\sin v}\le \frac{\pi}{2}\times\frac{u}{v},\text{ for }0 \le u < v \le \frac{\pi}{2}
v
u
≤
sin
v
sin
u
≤
2
π
×
v
u
,
for
0
≤
u
<
v
≤
2
π
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