已知a、b为常数,且a不等于0,函数f(x)=-ax+b+axlnx,f(e)=2,(e=2.71828...是自然对数的底数).(1)求实...已知a、b为常数,且a不等于0,函数f(x)=-ax+b+axlnx,f(e)=2,(e=2.71828...是自然对数的底数).(1)求实数b的的值.(2)
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![已知a、b为常数,且a不等于0,函数f(x)=-ax+b+axlnx,f(e)=2,(e=2.71828...是自然对数的底数).(1)求实...已知a、b为常数,且a不等于0,函数f(x)=-ax+b+axlnx,f(e)=2,(e=2.71828...是自然对数的底数).(1)求实数b的的值.(2)](/uploads/image/z/5225960-56-0.jpg?t=%E5%B7%B2%E7%9F%A5a%E3%80%81b%E4%B8%BA%E5%B8%B8%E6%95%B0%2C%E4%B8%94a%E4%B8%8D%E7%AD%89%E4%BA%8E0%2C%E5%87%BD%E6%95%B0f%28x%29%3D-ax%2Bb%2Baxlnx%2Cf%28e%29%3D2%2C%28e%3D2.71828...%E6%98%AF%E8%87%AA%E7%84%B6%E5%AF%B9%E6%95%B0%E7%9A%84%E5%BA%95%E6%95%B0%29.%281%29%E6%B1%82%E5%AE%9E...%E5%B7%B2%E7%9F%A5a%E3%80%81b%E4%B8%BA%E5%B8%B8%E6%95%B0%2C%E4%B8%94a%E4%B8%8D%E7%AD%89%E4%BA%8E0%2C%E5%87%BD%E6%95%B0f%28x%29%3D-ax%2Bb%2Baxlnx%2Cf%28e%29%3D2%2C%28e%3D2.71828...%E6%98%AF%E8%87%AA%E7%84%B6%E5%AF%B9%E6%95%B0%E7%9A%84%E5%BA%95%E6%95%B0%29.%281%29%E6%B1%82%E5%AE%9E%E6%95%B0b%E7%9A%84%E7%9A%84%E5%80%BC.%282%29)
已知a、b为常数,且a不等于0,函数f(x)=-ax+b+axlnx,f(e)=2,(e=2.71828...是自然对数的底数).(1)求实...已知a、b为常数,且a不等于0,函数f(x)=-ax+b+axlnx,f(e)=2,(e=2.71828...是自然对数的底数).(1)求实数b的的值.(2)
已知a、b为常数,且a不等于0,函数f(x)=-ax+b+axlnx,f(e)=2,(e=2.71828...是自然对数的底数).(1)求实...
已知a、b为常数,且a不等于0,函数f(x)=-ax+b+axlnx,f(e)=2,(e=2.71828...是自然对数的底数).(1)求实数b的的值.(2)求函数f(x)的单调区间
已知a、b为常数,且a不等于0,函数f(x)=-ax+b+axlnx,f(e)=2,(e=2.71828...是自然对数的底数).(1)求实...已知a、b为常数,且a不等于0,函数f(x)=-ax+b+axlnx,f(e)=2,(e=2.71828...是自然对数的底数).(1)求实数b的的值.(2)
f(e)=-ae+b+ae=2,则b=2.f'(x)=-a+a(1+lnx)=alna.
①a>0时,f(x)在(0,+∞)内递增;②a<0时,f(x)在(0,+∞)内递减.
2=-ae+b+ae;b=2;
求导f'(x)=-a+a+alnx=alnx;
lnx的单调区间是(负无穷,0)(0,正无穷)都为递增;
f(x)的单调区间(负无穷,0)(0,正无穷)都为递增。
(1) f(e)= -ae+b +ae =b=2 (2) f(x)= - ax+2+axlnx f(x)导函数=-a +alnx +a=alnx
当a>0时 x>1 f(x)导函数>0此时 原函数递增区间 (0 ,正无穷)递减区间(0,1)
当a
f(x)=-ax+b+axlnx
f(e)=-ae+b+ae=2
∴b=2
f(x)=-ax+axlnx+2
f(x)=axlnx/e+2
f(x)=ln(x/e)^ax+2
a>0,且x>e,f(x)增函数
0
0