x+{2/(x+1)}<7的解及是?要過程
熱心網(wǎng)友
變形為:(X2+X+2)/(X+1)<7,通分得:(X2-6X-5)/(X+1)<0 用穿線法先求出方程:(X2-6X-5)/(X+1)=0的根:X=3+根號(hào)14,X=3-根號(hào)14, X=-1,所以解集為:X<-1或(3-根號(hào)14) 上面的答案很對(duì) 當(dāng)x-1,x+{2/(x+1)}0,得x3+√14,∴x<-1所以原不等式的解集是:{x|x<-1或3-√14熱心網(wǎng)友
熱心網(wǎng)友