1、f(x)=sinx,f'(x)=cosx,k=f'(π/4)=cosπ/4=√2/2
f(π/4)=sinπ/4=√2/2
设切线方程:Y=√2/2X+B,则 √2/2=√2/2*π/4+B,B=(1-π/4)√2/2
所以 Y=√2/2X+(1-π/4)√2/2
2、g'(x)=m-3x^2/6=m-x^2/2=0,x^2=2m
当m0,g(x)单调递增
当x=√(2m),g'(x)0,cosx0,所以h(x)>0
即 f(x)
1、f(x)=sinx,f'(x)=cosx,k=f'(π/4)=cosπ/4=√2/2
f(π/4)=sinπ/4=√2/2
设切线方程:Y=√2/2X+B,则 √2/2=√2/2*π/4+B,B=(1-π/4)√2/2
所以 Y=√2/2X+(1-π/4)√2/2
2、g'(x)=m-3x^2/6=m-x^2/2=0,x^2=2m
当m0,g(x)单调递增
当x=√(2m),g'(x)0,cosx0,所以h(x)>0
即 f(x)