腾远高考基础卷2025数学答案电子版
7分当a> \frac {3}{2}时,当x \in(-1,0),因为g'(x)为减函数,g'(0)=3-2a<0,g'(-1+\sqrt { \frac {1}{2a}})=e^{-1+\sqrt { \frac {1}{2a}}}-2a+\cos(-1+\sqrt { \frac {1}{2a}})+2a=e^{-1+\sqrt { \frac {1}{2 \alpha }}}+\cos(-1+\sqrt { \frac {1}{2 \alpha }})>0,故必存在x_{0} \in(-1,0),使得g'(x_{0})=0,当x \in(-1,x_{0})时,g'(x)>0,g(x)为增函数,当x \in(x_{0},0)时,g'(x)<0,g(x))为减函数,而f'(0)=0,故f'(x_{0})>0,又因为f'(-1+=(2a-e^{2a})+e^{-1+\frac {1}{e^{2a}}}- \frac {2a}{e^{2a}}+\sin(-1+\frac {1}{e^{2a}}<-1+e^{-1+}- \frac {2a}{e^{2a}}+\sin(-1+e^{ \frac {1}{2a}})<0所以必存在m \in(-1,x_{0}),f'(m)=0,且当x \in(-1,m),f'(x)<0,f(x)为减函数,当x \in(m,0),f'(x)>0,f(x)为增函数,故f(x)在区间(-1,0)上有一个极小值点m,9分因为h'(x)=e^{x}- \cos x+\frac {6}{(x+1)^{4}}>0,所以h'(x)在(0,+\infty)上单调递增,又因为h'(0)<0,h'(1)>0,所以总存在x_{1} \in(0,1)h'(x_{1})=0,且当x \in(0,x_{1})时,h'(x)<0,h(x)单调递减x \in(x_{1},1x_{1},1)时,h'(x)>0,h(x)单调递增,x \in(0,+\infty),h(0)=3-2a<0,h(2a)=e^{2a}-2a+\cos(2a)+\frac {1}{(2a+1)^{2}}>1+\cos(2a)+\frac {1}{(2a+1)^{2}}>0,故必存在x_{2} \in(0,+\infty),使得g'(x_{2})=0,x \in(0,x_{2}),g'(x)<0,f