计算下列积分[tex=7.929x2.786]Rh48MD6bFp/GECAS00QJjCfo0ySKl9E5g4q8e1tWD0f4xgigU62aHL6WaQwFqZH7kvuNWKrq7H0v9xZmVmcrOg==[/tex]
计算下列积分[tex=7.929x2.786]Rh48MD6bFp/GECAS00QJjCfo0ySKl9E5g4q8e1tWD0f4xgigU62aHL6WaQwFqZH7kvuNWKrq7H0v9xZmVmcrOg==[/tex]
求直线在各坐标轴上的投影:[tex=7.929x2.786]fnpmC2J6JmQBLyo5NmGAzypV0RfDKP4ESpdGca76sguuNWlHjwxv8bcQtE4PVhIk231Ey7jv5cG3IPGljs4+FjTxRBgQaP9OPhIYEHWcscU=[/tex]。
求直线在各坐标轴上的投影:[tex=7.929x2.786]fnpmC2J6JmQBLyo5NmGAzypV0RfDKP4ESpdGca76sguuNWlHjwxv8bcQtE4PVhIk231Ey7jv5cG3IPGljs4+FjTxRBgQaP9OPhIYEHWcscU=[/tex]。
计算二阶行列式:[tex=7.929x2.786]mqOKs44jrJgbK/+3e5yEgfMRTxAEJFHlt6D6Tr7aCuFFMV/3H9yxr5fsoqYTR9eG8Dry/z9oDpY8qUCW5FY/MOTkyixktYZ2jBipW5M3NROarUcuLumdxOGoRuKeWHjmI18k+DpAeYzilmg24+df/Q==[/tex]。
计算二阶行列式:[tex=7.929x2.786]mqOKs44jrJgbK/+3e5yEgfMRTxAEJFHlt6D6Tr7aCuFFMV/3H9yxr5fsoqYTR9eG8Dry/z9oDpY8qUCW5FY/MOTkyixktYZ2jBipW5M3NROarUcuLumdxOGoRuKeWHjmI18k+DpAeYzilmg24+df/Q==[/tex]。
用点向式方程及参数方程表示直线[tex=7.929x2.786]fnpmC2J6JmQBLyo5NmGAzwyG3DULFwvpNilub4SRuV8tEj3JnQ0/hbHh87cQ+FX5ilOMeDI9zpLaOCQaRzN0BwioBBzqUTf/gaRsy2+uYyo=[/tex] .
用点向式方程及参数方程表示直线[tex=7.929x2.786]fnpmC2J6JmQBLyo5NmGAzwyG3DULFwvpNilub4SRuV8tEj3JnQ0/hbHh87cQ+FX5ilOMeDI9zpLaOCQaRzN0BwioBBzqUTf/gaRsy2+uYyo=[/tex] .
求点[tex=4.571x1.286]i4FNvHiXZ/EL3OfpBykowg==[/tex]到直线[tex=0.714x1.286]LA74ioWWkXdGbHCtFk/Sog==[/tex]:[tex=7.929x2.786]fnpmC2J6JmQBLyo5NmGAz1eqDScjjh+xasFpiMhfg/lrbIqnQEZatNxP6+5QFVSqLvFSyHWtWu5DiQCV+bUcIIlt3u0yfy8bt8GECPT7PRU=[/tex]的距离。
求点[tex=4.571x1.286]i4FNvHiXZ/EL3OfpBykowg==[/tex]到直线[tex=0.714x1.286]LA74ioWWkXdGbHCtFk/Sog==[/tex]:[tex=7.929x2.786]fnpmC2J6JmQBLyo5NmGAz1eqDScjjh+xasFpiMhfg/lrbIqnQEZatNxP6+5QFVSqLvFSyHWtWu5DiQCV+bUcIIlt3u0yfy8bt8GECPT7PRU=[/tex]的距离。
判断下面的序列是否是周期的; 若是周期的,确定其周期。 [tex=7.929x2.786]N/b0FGNnH7JVrl95ugLLk4FL1/YX/LcJPQeH23dIE/nNDs6GXhr7m2iTW8RTO7T9zH18w1ejrSGyoS8YgWPCAA==[/tex]
判断下面的序列是否是周期的; 若是周期的,确定其周期。 [tex=7.929x2.786]N/b0FGNnH7JVrl95ugLLk4FL1/YX/LcJPQeH23dIE/nNDs6GXhr7m2iTW8RTO7T9zH18w1ejrSGyoS8YgWPCAA==[/tex]
方程 [tex=6.929x1.429]dZVOZRwAFOvKp9AUaFOTZgPUyFqktBYrFH+NZFE/JUo=[/tex]的通解是 未知类型:{'options': ['[tex=3.857x2.5]jVKtN0a1khDLgiezkvn0f4JQwgcIOKbEzkPstbmySPg=[/tex]', '[tex=7.929x2.786]SnsauEuPeTehnA8Yocr6Dbe03xfiarxJN9eoUCEKvrCq4PAauZXWq0cnhopIRBhk/YF9Q95/ameHeiRx4IvSZg==[/tex]', '[tex=8.429x2.786]xehlaoMBYDwzLB99I0UVcq/wIX+X1iLiiyR1qr2B0uL7KSuEfgImTYjsKrD850V06QeBf19CI5T7i6L4buMRJw==[/tex]', '[tex=7.5x2.5]xehlaoMBYDwzLB99I0UVcgiwnXHt7sB0yHRPZv9KMt6YasK8YEtrvvg7UmQj3gHa[/tex]'], 'type': 102}
方程 [tex=6.929x1.429]dZVOZRwAFOvKp9AUaFOTZgPUyFqktBYrFH+NZFE/JUo=[/tex]的通解是 未知类型:{'options': ['[tex=3.857x2.5]jVKtN0a1khDLgiezkvn0f4JQwgcIOKbEzkPstbmySPg=[/tex]', '[tex=7.929x2.786]SnsauEuPeTehnA8Yocr6Dbe03xfiarxJN9eoUCEKvrCq4PAauZXWq0cnhopIRBhk/YF9Q95/ameHeiRx4IvSZg==[/tex]', '[tex=8.429x2.786]xehlaoMBYDwzLB99I0UVcq/wIX+X1iLiiyR1qr2B0uL7KSuEfgImTYjsKrD850V06QeBf19CI5T7i6L4buMRJw==[/tex]', '[tex=7.5x2.5]xehlaoMBYDwzLB99I0UVcgiwnXHt7sB0yHRPZv9KMt6YasK8YEtrvvg7UmQj3gHa[/tex]'], 'type': 102}
证明:只用行的初等变换以及对换某两列,任意[tex=2.714x1.071]wpWbdZdAiczlr4u40VpV3A==[/tex]矩阵[tex=0.786x1.0]Yn3GgEZev6SOu2r4v1WnCw==[/tex]都可以化为[tex=7.929x2.786]075gCzZzsMRb6HYXYk9X95G9a4XmqWh5rHV2AhbZhou39k4cpE8ZuEJFZ4ZxTH/Yupryq0onV14S97qnVGHh/jOPdg2USgL2/EjZzOUK7AI=[/tex]其中[tex=4.357x1.0]akDE3bSvxe0s1vO9enpAs0pxKsTqGXhydJKXEhXstTI=[/tex]。
证明:只用行的初等变换以及对换某两列,任意[tex=2.714x1.071]wpWbdZdAiczlr4u40VpV3A==[/tex]矩阵[tex=0.786x1.0]Yn3GgEZev6SOu2r4v1WnCw==[/tex]都可以化为[tex=7.929x2.786]075gCzZzsMRb6HYXYk9X95G9a4XmqWh5rHV2AhbZhou39k4cpE8ZuEJFZ4ZxTH/Yupryq0onV14S97qnVGHh/jOPdg2USgL2/EjZzOUK7AI=[/tex]其中[tex=4.357x1.0]akDE3bSvxe0s1vO9enpAs0pxKsTqGXhydJKXEhXstTI=[/tex]。
已知序列[tex=1.929x1.357]YN2aXOpa/g9sSaYjsbft0Q==[/tex]的[tex=0.857x1.0]+NBI8Pm2vVS+bGgOpHKyOA==[/tex]点 DFT 为[tex=2.5x1.357]OkuVFNHzxX+AJun4LnlhLw==[/tex],利用 DFT 的移频特性求下列序列的 DFT。[tex=7.929x2.786]fWYj+YHWJ0xD8ZCS6tIx4eyvIyUBRTi6zgSo6tcU1NOJGBGiKiuYqX/MoAgb6ZdYhI/AakInwJCgpvJsMzfJlA==[/tex]
已知序列[tex=1.929x1.357]YN2aXOpa/g9sSaYjsbft0Q==[/tex]的[tex=0.857x1.0]+NBI8Pm2vVS+bGgOpHKyOA==[/tex]点 DFT 为[tex=2.5x1.357]OkuVFNHzxX+AJun4LnlhLw==[/tex],利用 DFT 的移频特性求下列序列的 DFT。[tex=7.929x2.786]fWYj+YHWJ0xD8ZCS6tIx4eyvIyUBRTi6zgSo6tcU1NOJGBGiKiuYqX/MoAgb6ZdYhI/AakInwJCgpvJsMzfJlA==[/tex]
设 [tex=3.714x1.214]DHtnfSoh6bzU7RVzArKzTN9lLnnXrxk5tvdejbqeTm8=[/tex], 又[tex=7.929x2.786]80Wj0uAKV+7pqHZEfv32mMcC7kUILtDqVZ6LHnjKWcm5ZYM/mwDI+W/lSRo7uHB1Dj6170QUps/CbNWbVeQK6oCxayJpEZvY2XNAFyL6tW9WqhmU0aMCXyEIx1wAH7yn[/tex], [tex=18.214x1.357]asXUOYddKc57fCVzYaZ6jPyXIAZ78u01hBhTzXO5FYEOZQuHlE3CN4FmEFtwmZmQhOtqVp2b4JoxSHmiWy/kXivxyOPwh91Lr6SzMAoKYv3juZcgn1TRfx7AW03g1kC4POXnZ4uRwCNSY+7tBl8cvqZqTDLHBtJwpAMRnlbpniE=[/tex].则存在正交矩阵 [tex=0.786x1.286]dSWbQCTjdbLxKy7q0ps2gg==[/tex] 使得[p=align:center][tex=7.143x2.786]z6dVk/ZZeap1XeWgy3TquY8Yu/gksRxLGT8edb7LTL98aYVbh25jvWw99pDTwnjAWrkYJk8o6kc9zf/ySDhPxYkTET379wd7RUgKV3qHqyA=[/tex].
设 [tex=3.714x1.214]DHtnfSoh6bzU7RVzArKzTN9lLnnXrxk5tvdejbqeTm8=[/tex], 又[tex=7.929x2.786]80Wj0uAKV+7pqHZEfv32mMcC7kUILtDqVZ6LHnjKWcm5ZYM/mwDI+W/lSRo7uHB1Dj6170QUps/CbNWbVeQK6oCxayJpEZvY2XNAFyL6tW9WqhmU0aMCXyEIx1wAH7yn[/tex], [tex=18.214x1.357]asXUOYddKc57fCVzYaZ6jPyXIAZ78u01hBhTzXO5FYEOZQuHlE3CN4FmEFtwmZmQhOtqVp2b4JoxSHmiWy/kXivxyOPwh91Lr6SzMAoKYv3juZcgn1TRfx7AW03g1kC4POXnZ4uRwCNSY+7tBl8cvqZqTDLHBtJwpAMRnlbpniE=[/tex].则存在正交矩阵 [tex=0.786x1.286]dSWbQCTjdbLxKy7q0ps2gg==[/tex] 使得[p=align:center][tex=7.143x2.786]z6dVk/ZZeap1XeWgy3TquY8Yu/gksRxLGT8edb7LTL98aYVbh25jvWw99pDTwnjAWrkYJk8o6kc9zf/ySDhPxYkTET379wd7RUgKV3qHqyA=[/tex].