Question

设x>0,y>0,且x2+y2/2=1,求x*跟下1+y2的最大值

Answer 1

x2+y2/2=1,求x√1+y2最大值x²+y²/2=1 2x²+y²=2 2x²+y²+1=3 即2x²与(1+y²)的和为定值 [x*√(1+y²)]² =x²*(1+y²) =(1/2)*2x²*(1+y²) ≤(1/2)*...