aika
设A是实对称矩阵,且A^2=0,证明:A=0
A是实对称矩阵 A=﹙aij﹚ aij=aji 从aij=0 可得aij=0看A的i行i列交点元素﹙A﹚ii=∑[1≤k≤n]aikaki=∑[1≤k≤n]aikaik=∑[1≤k≤n]aik=0[∵A...
证明设n阶行列式Dnn,D中元素aij的代数余子式Aij.证明...
这道题n阶行列式D应该不为0.行列式的性质中有这样一个:求和(k从1到n)aikAik=D(行列式),求和(k从1到n)aikAjk=0,利用这个性质,把向量(An1,...,Ann)代入上述方程...
www.haodf.com/wenda/caikaican - g - 654602600.htm
Dr.Poole says that she (66)___tell the difference between Mlaika's call and the (67)___(distance)truck noise.Why did (68)___copy the sounds of the trucks ...
heyuanlaishiwodecuonameduibuqiyihoubuyaozaikaojin...
呵 原来是我的错 那么对不起 以后不要再靠近 拜~
People can often see a talking parrot on a TV show...
Dr.Poole says that she couldn't tell the difference between Mlaika's call and the(67)___(distance) truck noise.Why did(68)___ copy the sounds of the trucks ...