5.若p是真命题,q是假命题,则( )
| A. | p且q是真命题 | B. | p或q是假命题 | C. | 非p是真命题 | D. | 非q是真命题 |
3.点P在曲线y=x3-x+7上移动,过点P的切线倾斜角的取值范围是( )
| A. | [0,π] | B. | $[0,\frac{π}{2})∪[\frac{3π}{4},π)$ | C. | $[0,\frac{π}{2})∪[\frac{π}{2},π)$ | D. | $[0,\frac{π}{2}]∪[\frac{3π}{4},π)$ |
19.曲线y=3sin2x图象上所有点的横坐标伸长为原来的2倍,纵坐标变为原来的$\frac{1}{3}$倍,所得图象对应的解析式为( )
| A. | y=9sin4x | B. | y=sin4x | C. | y=9sinx | D. | y=sinx |
18.设f(x)=$\sqrt{{x^2}+1}$,则f′(2)=( )
0 238293 238301 238307 238311 238317 238319 238323 238329 238331 238337 238343 238347 238349 238353 238359 238361 238367 238371 238373 238377 238379 238383 238385 238387 238388 238389 238391 238392 238393 238395 238397 238401 238403 238407 238409 238413 238419 238421 238427 238431 238433 238437 238443 238449 238451 238457 238461 238463 238469 238473 238479 238487 266669
| A. | $\frac{{\sqrt{5}}}{5}$ | B. | $-\frac{{\sqrt{5}}}{5}$ | ||
| C. | $\frac{{2\sqrt{5}}}{5}$ | D. | $\frac{{-2xsinx-(1-{x^2})}}{sinx}$ |