1.

`lim_(xrarr -1) (cos 2 -cos 2x)/(x^2-|x|)` is equaol toA. 2B. `sin 2`C. `2sin2`D. none of these

Answer» Correct Answer - C
We have,
`lim_(xto -1) (cos 2 -cos 2x)/(x^2-|x|)`
` =lim_(xto-1)(2sin(1+x)sin(x-1))/(x^2+x)[because |x|=-x " for " x lt 0]`
` =2 lim_(xto-1) (sin(xto1))/(xto1)xx(sin(x-1))/(x)`
` =2xx1 xx(sin(-2))/((-1))=2sin 2`.


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