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Grade 12Differential Calculus

Lim(x tends to infinity)(sin-1x-tan-1 x)2/xn exists for maximum value of n, is

a. n=2

b.n=3

c.n=6

d.No such value of n is possible

Profile image of Vaibhav Mathur
16 Years agoGrade 12
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1 Answer

Profile image of Ramesh V
16 Years ago

For any values of x , sin-1x  lies in ( -Pi/2, Pi/2 )

also ,  -Pi/2 <  tan-1x  < Pi/2

and here as x tends to infinity , tan-1x = Pi/2

therefore, as x tends to infinity , (sin-1x - tan-1x)2 becomes some positive number( >=0 )

also xn goes to +infinity for any value of n(n>0)

so, the final limit to zero ( i.e., limit exists ) for all n>0

from the options max alue of n is 6

so,option C

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