若向量[img=27x29]1803bbf1e1cd681.png[/img]，且向量[img=115x29]1803bbf1e945ae2.png[/img],[img=35x24]1803bbf1f13de8a.png[/img]= - 18,则[img=29x19]1803bbf1fc71fcd.png[/img]( )
A: (4,-2,-4)
B: (-4,-2,-4)
C: (-4,2,4)
D: (4,-2,4)
A: (4,-2,-4)
B: (-4,-2,-4)
C: (-4,2,4)
D: (4,-2,4)
举一反三
- 若向量[img=27x29]1803bbf0a3a1732.png[/img]，且向量[img=115x29]1803bbf0ab97983.png[/img],[img=35x24]1803bbf0b543bb7.png[/img]= - 18,则[img=29x19]1803bbf0bd455ca.png[/img]( ) A: (4,-2,-4) B: (-4,-2,-4) C: (-4,2,4) D: (4,-2,4)
- 求不定积分[img=112x35]17da6538063a9e4.png[/img]； （ ） A: (x^4*log(x)^2)/4 + (x^4*(log(x) - 1/4))/ B: (x^4*log(x)^2)/4 - (x^4*(log(x) - 1/4))/8 C: (x^4*log(x)^2)/4 - (x^4*(log(x) - 1/4)) D: (x^4*log(x)^2)/4 + (x^4*(log(x) - 1/4))/8
- 求函数[img=173x42]17da65390bf2806.png[/img]的导数； ( ) A: tan(pi/4 + x/2) B: (tan(pi/4 + x/2)^2/2 ) /tan(pi/4 ) C: (tan(pi/4 + x/2)^2/2 + 1/2) D: (tan(pi/4 + x/2)^2/2 + 1/2) /tan(pi/4 + x/2)
- 随机变量X的概率密度为[img=239x61]1803915d900b3cb.png[/img]则常数c为 A: 2 B: [img=98x52]1803915d9894210.png[/img] C: 1 D: 3 E: 4 F: 1/2 G: 1/3 H: 1/4
- 随机变量X的概率密度为[img=239x61]1802d3e895f944e.png[/img]则常数c为 A: 2 B: [img=98x52]1802d3e89f1fea8.png[/img] C: 1 D: 3 E: 4 F: 1/2 G: 1/3 H: 1/4