ctgx + cosx = 1+
ctg*cosx
First we will rewrite the
identities.
We know
that:
ctg(x) =
cosx/sinx.
==> cosx/sinx + cosx = 1 + cosx/sinx *
cosx
Now we will
simplify.
==> (cosx + cosx*sinx)/sinx = 1+
1/sinx
==> We will multiply by
sinx.
==> cosx + cosx*sinx = sinx +
1
Now we will move all terms to the left
side.
==> cosx + cosx*sinx - sinx -1 =
0
Now we will facotr cosx and -1
.
==> cosx ( 1+ sinx ) -1 ( sinx+ 1) =
0
Now we will factor
(1+sinx)
==> (1+sinx) (cosx -1) =
0
==> sinx +1 = 0 ==> sinx = -1 ==> x
= 3pi/2 + 2npi
==> cosx -1 = 0==> cosx = 1
==> x = 0+2npi, pi+2npi, 2pi+2npi
Then the answer
is:
x = { 2npi, 3pi/2+2npi } n= 0, 1, 2,
3,....
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