(2014•宜宾二模)已知cos(π4
(2013•宜宾二模)已知函数ft(x)=11+x−1(1+x)2(t-x),其中t为正常数.
(2013•莱芜二模)已知函数f(x)=22cos(x+π4)cos(x−π4)+22sinxcosx.
(2013•宜宾二模)已知函数f(x)=−x2−2x+a(x<0)f(x−1)(x≥0),且函数y=f(x)-x恰有3个
(2013•内江二模)已知cosα=35(0<α<π)
(2014•济南二模)已知函数f(x)=cos(π4x-π3)+2cos2π8x.
(2014•石家庄二模)已知函数f(x)=cos(x+π4)•sinx,则函数f(x)的图象( )
(2014•广州二模)已知函数f(x)=2cos(x+π4),x∈R.
(2013•虹口区二模)已知.cosαsinαsinβcosβ.=13
(2009•崇明县二模)函数y=2cos(x+π4)cos(π4−x)
(2011•绵阳二模)已知函数f(x)=sin x-cos (x-π6
(2014•温州二模)已知函数f(x)=sin(x+π)cos(π−x),则下列结论中正确的是( )
(2012•怀化二模)已知函数f(x)=23sin(x2+π4)cos(x2+π4)−sin(x+π).