2021-2022 英语周报 九年级 课标 3答案

18.【解析】(1)证明:连接BQ,由题意知PD⊥平面BMQN,所以BQ⊥PD,生正2分因为在△PBD中,BD=PB=PD=22,所以Q为PD的中点,…因为PE=3ED,所以DE=40D=PD=DE=0=PD=+m=0=+03分即QE=ED5分因为B0=OD,所以OE∥BQ,…6分因为OE平面BMQN,所以OE∥平面BMQNPC+PD2-CD2_(22)2+(222)-4(2)在△PCD中,cos∠CPD=2×22×22在Rt△PNQ中,∠NQP=,cos∠QPN=所以PN=CN=PC-PN=7分即点N为线段PC上靠近C的三等分点以O为原点,建立如图所示的空间直角坐标系则0(0,0,0),A(0,-2,0),B(2,0,0),C(0,2,0),D(-2,.0,0),P(0,0,6),分(-2=(-2,-236)48=(,2,0A=(0,设平面PAB的法向量为n=(x,y,z),=0则取z=1,n=(3,-3,1)10分√2取z=1,n=(3,-3,1)……10分y+√6z=0设直线NQ与平面PAB所成角为6则0=1c0,m>}=m0。6…11分综上,直线M0与平面PAB所成角的正弦值为点12分

第二节:参考范文I couldn t belieze it! I wasn t punished and I got my very own bird field guide. It s the very one that I hadbeen saving up money to buy. Then, I gave the money I had to my teacher to help buy a new window. But shekept refusing tmy ideal, saying I should spend the tmoney buying some necessities of study. So after school. Iwent home with my own field guide and a new motivation.No, many years hazr passed. The look is still in my drawer. but my wonderful teacher hasway. Thanks to her reward and encouragement. I l ecome the man who i want. All of that day that remains ismy memory and the lesson my teacher taught me. That lesson stays with me every day and I will remember itforever. Im so lucky to have met such a great teacher.评分原则1.本题总分为25分,按5个档次给分2.评分时,先根据所续写短文的内容和语言初步确定其所属档次,然后以该档次的要求来衡量、确定或调整档次,最后给分3.词数少于130的,从总分中减去2分1.评分时,应主要从以下四个方面考虑:

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