已知函数f(x)=kx^3-3(k+1)x^2-k^2+1(k>0),函数f(x)的单调减区间为(0,4),当x>k,求证2√x>3-1/x
已知函数f(x)=kx^3-3(k+1)x^2-k^2+1(k>0),函数f(x)的单调减区间为(0,4),当x>k,求证2√x>3-1/x
数学人气:350 ℃时间:2020-04-05 22:59:53
优质解答
f'(x)=3kx^-6(k+1)x=0,x1=0,x2=2(k+1)/k,k>0,f(x)在(x1,x2)上递减,其余情况递增,已知f(x)的单调减区间为(0,4),∴2(k+1)/k=4,k+1=2k,k=1.f(x)=x^3-6x^2,x>k=1时2√x>3-1/x,①平方得4x>9-6/x+1/x^2,4x^3>9x^2-6x+1,4x...
我来回答
类似推荐
猜你喜欢
- 1如图,AB是圆O的直径,C是圆O上一点,∠BAC=2∠B,圆O的切线AP与OC的延长线相交于点P,已知PA=6根号3,求AC的长
- 2如图,在平面直角坐标系中,有若干个横坐标分别为整数的点,其顺序按图中“→”方向排列,如(1,0),(
- 3(x+5)(x+6)(x+10)(x+12)-2x^2 因式分解
- 4从划线句中 你读到了什么
- 5I don't suppose he will attend the meeting,_______?
- 6“专心” 近义词
- 7Everyone in school should obey the rules._____ _____ us should obey the rules.
- 8用漠不关心和麻木不仁两个词 共同造句50
- 9若正数a.b满足a^2/(a^4+a^2+1)=1/24,b^3/(b^6+b^3+1)=1/19,则ab/(a^2+a+1)(b^2+b+1)=
- 10关于乙醇的结构式中的相关问题.