Возводим в квадрат:
16х=4x^2+4x+1
4x^2-12x+1=0
D=144-16=128
sqrt(128)=8sqrt(2)
x_(1)=(12-8sqrt(2))/8=1,5-sqrt(2); x_(2)=(12+8sqrt(2))/8=1,5+sqrt(2)
[m]S= ∫^{1,5+\sqrt{2}}_{1,5-\sqrt{2}}(4\sqrt(x)-2x-1)dx=4\cdot( \frac{x^{\frac{3}{2}}}{\frac{3}{2}}-x^2-x)|^{1,5+\sqrt{2}}_{1,5-\sqrt{2}}=...[/m]