Question 1027543
Which is the shaded region. 
Outside the square?
If so, the diagonal of the square is equal to the diameter of the circle.
{{{D[s]=D[c]}}}
{{{S[s]=D[s]/sqrt(2)}}}
{{{A[s]=S[s]^2=D[s]^2/2}}}
{{{A[c]=(pi/4)D[c]^2}}}
So then,
{{{A=A[c]-A[s]}}}
{{{A=(pi/4)D[c]^2-D[c]^2/2}}}
{{{A=D[c]^2(pi/4-1/2)}}}
{{{A=(2R[c])^2(pi/4-1/2)}}}
{{{A=R[c]^2(pi-2)}}}
You can substitute for R to get the final answer.