(5/1-sin(x))+(5/1+sin(x))
The common denominator will be (1-sin x)(1+sinx)
Multiply the first fraction top and bottom by (1+sinx) and multiply the second fraction top and bottom by (1-sinx)
(5(1+sinx) +5(1-sinx))/(1-sinx)(1+sinx)
Distribute top and bottom
(5 + 5sin x + 5 -5sinx)/1-sin2x
Combine like terms
The answer is
10/cos2x
Because the identity sin2 x + cos2x=1
Subtracting sin2 x from both sides yields
Cos2x=1-sin2x