景德镇市2023届高三第三次质检文综

23.解:(1)当a=-1时,f(x)=|3x+1|-2.由|3x+1-2≤5,整理得-7≤3x+1≤7,……2分解得-≤x≤2,因此不等式f(x)≤5的解集为{x-≤x≤21分(2)当x∈R时,f(x)+3g(x)=|3x-a|+2a+|3x-3≥|3x-a-3x+3|+2a=|3-a|+2a6分当x=1时等号成立,所以当x∈R时,f(x)+3g(x)≥9等价于|3-a|+2a≥9.①7分当a≤3时,①等价于a+3≥9,无解;……8分当a>3时,①等价于a-3+2a≥9,解得a≥49分所以a的取值范围是[4,+∞)10分评分细则:(1)第一问中,在求不等式∫(x)≤5的解集时,去掉绝对值得2分,第一问全部正确得4分.(2)第二问中,写出f(x)+3g(x)的最小值得2分,后续步骤每讨论一种情况各得2分.

第三节One possible versionParagraph 1As the cashier put the DVD into a plastic bag, / walkeder to the younger woman. "Is that your mom? "I askedhalfway expecting her to tell me it was none of my businessBut she rolled her eyes and said, "Yeah. "I smiled toshow her I wasn't criticizing.Cherish her, "I said. Andn I answered her curious expression by saying, "Whenshes gone, it's the little moments like this that'llcomeack to you. " It was true. I missed my mother still andremembered the moments when I was so impatient as tomake her life miserableParagraph 2The elderly woman moved with her deliberate slownessback to her daughter. Together they made their way towardsthe exit of the video store. They stood there for a momentside bywaiting for the rushing holiday current and foin it. Then the daughter glanced over andmomentarily regarded her mother. And slowly, almostreluctantly, she placed her arm with apparently unaccus.tomed affection around her mother's shoulders and gentlguided her back into the deluge.