대답:
#lim_ (x-> 0) x / sqrt (1-cos (x)) = sqrt (2) #
설명:
(x -> 0) x / sqrt (1-cos (x)) #
sqrt (1 + cos (x)) * sqrt (1 + cos (x)) / sqrt (1 + cos (x)
(x -> 0) (xsqrt (1 + cos (x)) / sqrt (1-cos ^ 2 (x)) #
# = lim_ (x-> 0) (xsqrt (1 + cos (x))) / sin (x) #
# = lim_ (x-> 0) x / sin (x) sqrt (1 + cos (x)) #
# = lim_ (x-> 0) x / sin (x) * lim_ (x-> 0) sqrt (1 + cos (x)) #
# = 1 * sqrt (2) #
# = sqrt (2) #
