求下面均匀密度的平面薄板重心.高为 [tex=0.571x1.286]x194220Kn6/AuOngnKO24Q==[/tex], 底分别为 [tex=0.571x1.286]mRKL/orzOudCEARA8qn3Kw==[/tex] 和 [tex=0.5x1.286]PGyKeLDo0qv9T0n29ldi6w==[/tex] 的等腰梯形.
举一反三
- 设[tex=0.571x1.286]mRKL/orzOudCEARA8qn3Kw==[/tex],[tex=0.5x1.286]PGyKeLDo0qv9T0n29ldi6w==[/tex]是有理数,满足[tex=9.214x2.929]wLLnuhaTkejykG34Lose4Gk3bDdglgIOUPyksgtxtXmt1sHAbktViJ8p1ePynplK3+wsNPKnCMhi2L94ONh39NTRjZdrdBEvRo1TQVd9L2o=[/tex],求[tex=0.571x1.286]mRKL/orzOudCEARA8qn3Kw==[/tex],[tex=0.5x1.286]PGyKeLDo0qv9T0n29ldi6w==[/tex]的值。
- 随机变量[tex=0.5x1.286]cFLrzlMvECfU5CTqcvierw==[/tex]分别以概率0.4、[tex=0.571x1.286]mRKL/orzOudCEARA8qn3Kw==[/tex]、[tex=0.5x1.286]PGyKeLDo0qv9T0n29ldi6w==[/tex]和[tex=0.5x1.286]m/VGGUpsnKNFGYXigdTc/A==[/tex]取值1、2、3、4,并且[tex=3.071x1.286]fknOBgzbjEu52cPH0WBW3g==[/tex],[tex=3.071x1.286]UAJJxdfCoB8SKuppr0cT/w==[/tex].求[tex=0.571x1.286]mRKL/orzOudCEARA8qn3Kw==[/tex],[tex=0.5x1.286]PGyKeLDo0qv9T0n29ldi6w==[/tex]、[tex=0.5x1.286]m/VGGUpsnKNFGYXigdTc/A==[/tex]。
- 已知:直线[tex=0.571x1.286]mRKL/orzOudCEARA8qn3Kw==[/tex]、[tex=0.5x1.286]PGyKeLDo0qv9T0n29ldi6w==[/tex]、[tex=0.5x1.286]m/VGGUpsnKNFGYXigdTc/A==[/tex]、[tex=0.571x1.286]E8TCNnEPtMKJ0mC2xxh0/Q==[/tex]是两两相交且不过同一点的四条直线,求证:直线[tex=0.571x1.286]mRKL/orzOudCEARA8qn3Kw==[/tex]、[tex=0.5x1.286]PGyKeLDo0qv9T0n29ldi6w==[/tex]、[tex=0.5x1.286]m/VGGUpsnKNFGYXigdTc/A==[/tex]、[tex=0.571x1.286]E8TCNnEPtMKJ0mC2xxh0/Q==[/tex]共面。
- 如果正数[tex=0.571x1.286]mRKL/orzOudCEARA8qn3Kw==[/tex],[tex=0.5x1.286]PGyKeLDo0qv9T0n29ldi6w==[/tex],[tex=0.5x1.286]m/VGGUpsnKNFGYXigdTc/A==[/tex],[tex=0.571x1.286]E8TCNnEPtMKJ0mC2xxh0/Q==[/tex]满足[tex=6.143x1.286]ZmgY4IYKNAnTxjSaOa1RjQ==[/tex],那么 未知类型:{'options': ['[tex=4.429x1.286]LJI1FiqfFfvLk57V4PrnIg==[/tex],且等号成立时[tex=0.571x1.286]mRKL/orzOudCEARA8qn3Kw==[/tex],[tex=0.5x1.286]PGyKeLDo0qv9T0n29ldi6w==[/tex],[tex=0.5x1.286]m/VGGUpsnKNFGYXigdTc/A==[/tex],[tex=0.571x1.286]E8TCNnEPtMKJ0mC2xxh0/Q==[/tex]的取值唯一', '[tex=4.429x1.286]TX9Qz0sE7bWEvnntsBl/HA==[/tex],且等号成立时[tex=0.571x1.286]mRKL/orzOudCEARA8qn3Kw==[/tex],[tex=0.5x1.286]PGyKeLDo0qv9T0n29ldi6w==[/tex],[tex=0.5x1.286]m/VGGUpsnKNFGYXigdTc/A==[/tex],[tex=0.571x1.286]E8TCNnEPtMKJ0mC2xxh0/Q==[/tex]的取值唯一', '[tex=4.429x1.286]LJI1FiqfFfvLk57V4PrnIg==[/tex],且等号成立时[tex=0.571x1.286]mRKL/orzOudCEARA8qn3Kw==[/tex],[tex=0.5x1.286]PGyKeLDo0qv9T0n29ldi6w==[/tex],[tex=0.5x1.286]m/VGGUpsnKNFGYXigdTc/A==[/tex],[tex=0.571x1.286]E8TCNnEPtMKJ0mC2xxh0/Q==[/tex]的取值不唯一', '[tex=4.429x1.286]TX9Qz0sE7bWEvnntsBl/HA==[/tex],且等号成立时[tex=0.571x1.286]mRKL/orzOudCEARA8qn3Kw==[/tex],[tex=0.5x1.286]PGyKeLDo0qv9T0n29ldi6w==[/tex],[tex=0.5x1.286]m/VGGUpsnKNFGYXigdTc/A==[/tex],[tex=0.571x1.286]E8TCNnEPtMKJ0mC2xxh0/Q==[/tex]的取值不唯一', '以上均不正确'], 'type': 102}
- 边长为[tex=0.571x1.286]mRKL/orzOudCEARA8qn3Kw==[/tex]和[tex=0.5x1.286]PGyKeLDo0qv9T0n29ldi6w==[/tex]的矩形薄板,与液面成角[tex=0.643x1.286]vYiGJJ9TAtvnQmM1PsOB8g==[/tex]斜沉于液体内,边长平行与液面而位于深[tex=0.571x1.286]x194220Kn6/AuOngnKO24Q==[/tex]处,设[tex=2.286x1.286]I+MrHg3a6txKkV+xXAeQOQ==[/tex],液体的比重为[tex=0.571x1.286]M+eYpqilGvF5SR20x91zcw==[/tex],试求薄板每面所受的压力。