(1/2) ×(√8 )-(√0.5 )-[√(4+1/2)]+2(√50)=(1/2) ×(2√2)-(√2/2)-[(3√2)/2]+(10√2)=(11√2)-(2√2)=9√2文字叙述：二分之一乘以根号8-根号0.5-根号下4又二分之一+2倍根号50=二分之一乘以2倍根号2-二分之根号...