1.

number of real solutions of the equation `|cotx|= cotx + 1/ sin x` `(0

Answer» `|cotx| = cotx +1/sinx`
`cotx` will be positive when `x in (0,pi/2)`.
`:. x in (0,pi/2)`,
`cotx = cotx +1/sinx`
`=>1/sinx = 0`
`=>sinx = oo`
We know, maximum value of `sin x` is `1.`
So, no solution possible when `x in (0,pi/2)`.
`cotx` will be negative when `x in (pi/2,pi)`.
`:. x in (pi/2,pi)`,
`-cotx = cotx +1/sinx`
`=>-2cotx = 1/sinx`
`=>-2cosx/sinx = 1/sinx`
`=>cosx = -1/2`
`=>x = (2pi)/3`
So, `x = (2pi)/3` is the only solution available for the given equation.
`:.` Number of solutions for this equation is `1`.


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