giải pt và bất pt sau

` a)(x-4)(x-3)(x+2)=0 `

` => ` \(\left[ \begin{array}{l}x-4=0\\x-3=0\\x+2=0\end{array} \right.\) 

` => ` \(\left[ \begin{array}{l}x=4\\x=3\\x=-2\end{array} \right.\) 

` =>x in {4;3;-2} `

` b)|x-3|=12-2x `

` ĐKXĐ:12-2x≥0=>2x≤12=>x≤6 `

` => ` \(\left[ \begin{array}{l}x-3=12-2x\\x-3=2x-12\end{array} \right.\) 

` => ` \(\left[ \begin{array}{l}x+2x=12+3\\x-2x=-12+3\end{array} \right.\) 

` => ` \(\left[ \begin{array}{l}3x=15\\-x=-9\end{array} \right.\) 

` => ` \(\left[ \begin{array}{l}x=5(TM)\\x=9(KTM)\end{array} \right.\) 

` =>x=5 `

` c)1/(x-1)-2/(2-x)=5/((x-1)(x-2)) `

` =>(x-2)/((x-1)(x-2))-(-2(x-1))/(-(x-1)(2-x))=5/((x-1)(x-2)) `

` =>(x-2)/((x-1)(x-2))-(-2x+2)/((x-1)(x-2))=5/((x-1)(x-2)) `

` =>(x-2)-(-2x+2)=5 `

` =>x-2+2x-2=5 `

` =>(x+2x)-(2+2)=5 `

` =>3x-4=5 `

` =>3x=9=>x=3 `

` d)(x-5)/5<(x-7)/3 `

` =>3(x-5)<5(x-7) `

` =>3x-15<5x-35 `

` =>3x-5x<-35+15 `

` =>-2x<-20 `

` =>2x>20=>x>10 `