We'll start with the denominator of the first fraction and
we'll open the brackets of radicand.
sqrt[1-(sin x)^2-(sin
x)^2*(cosx)^2]
From Pythagorean theorem,we'll
get:
1-(sin
x)^2=(cosx)^2
sqrt[1-(sin x)^2-(sin
x)^2*(cosx)^2]=sqrt[(cosx)^2-(sin
x)^2*(cosx)^2]
sqrt[(cosx)^2-(sin
x)^2*(cosx)^2]=sqrt(cosx)^2*[1-(sin
x)^2]
sqrt(cosx)^2*[1-(sin x)^2] =
sqrt[(cosx)^2*(cosx)^2]=(cosx)^2
The first fraction inside
brackets will become:
1/sqrt[1-(sin
x)^2*(1+(cosx)^2)]=1/(cosx)^2 (1)
We'll do the
same steps for the 2nd fraction.
sqrt[1-(cos x)^2-(sin
x)^2*(cos x)^2]
From Pythagorean theorem,we'll
get:
1-(cos x)^2 = (sin
x)^2
sqrt[1-(cos x)^2-(sin x)^2*(cos x)^2]=sqrt[(sin
x)^2-(sin x)^2*(cos x)^2]
sqrt[(sin x)^2-(sin x)^2*(cos
x)^2]=sqrt(sin x)^2*[1-(cos x)^2]
sqrt(sin x)^2*[1-(cos
x)^2]=sqrt[(sin x)^2*(sin x)^2]=(sin x)^2
The second
fraction will
become:
1/sqrt[1-(cosx)^2*(1+(sinx)^2)]=1/(sin x)^2
(2)
We'll re-write the expression, replacing the
fractions by (1) and (2):
E = (sin
x)^2*(cosx)^2*[1/(cosx)^2 + 1/(sin x)^2]
E = (sin
x)^2*(cosx)^2*[(sin x)^2+(cosx)^2]/(cosx)^2*(sin x)^2
But
(sin x)^2+(cosx)^2=1
E = (sin x)^2*(cosx)^2/(cosx)^2*(sin
x)^2
E = 1
The
requested simplified expression is: E =
1.
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