Derivative

1003112007

Level: 
A
Which of the statements A, B, C, D given bellow are correct? A:  (3x3−5x2+7x)′=9x2−10x+7, x∈RB:  (x2+2x−2−5)′=2x−4x−3, x∈R∖{0}C:  (5x4−7x3+2π)′=20x3−21x2+2, x∈RD:  (x4−4x4)′=4x3−16x3, x∈R∖{0} The only correct statements are:
A, B
A, C
A, B, C
A, D
A, C, D

1003112009

Level: 
A
Which of the statements A, B, C, D given bellow are incorrect? A:  (x−cos⁡⁡x+ln⁡x)′=12x+sin⁡x+1x, x∈R+B:  (3sin⁡x−3x+x3)′=3cos⁡x−3x+3x2, x∈RC:  (cotgx−log35)′=−1sin2⁡x, x∈R∖⋃k∈Z{kπ}D:  (3x23−2ex)′=2x3−2ex, x∈R∖{0} The only incorrect statements are:
B
B, C
A, B, C
C, D
B, C, D
C