12/1- Warmup

What should "du" equal in this integral?

• tanxsecx dx
• secx dx
• sec²x dx
• tanx dx

∫ 6 x (x² +1 )² dx

• ( x² + 1)³ + C
• 3 ( x² + 1)³ + C
• ( x² + 1)¹ + C
• 6 ( x² + 1)³ + C

∫ 2x cos(x²) dx

• sin(x²) + C

• 2 sin ( 2x ) + C

• (1/2) sin(x²) + C

• 4 cos(2x ) + C

∫5 e^5x dx

• 25 e^5x + C 
• 5 e^{5x - 1} + C 
• e^5x +  C 
• (1/5) e^5x + C 

What should "u" equal in this integral?

• x
• (lnx)/x
• lnx
• sin(lnx)

• ln(2x²+6) + C
• ln(2x²+6)(4x) + C
• 1/(2x²+6) + C
• 1/(2x²+6)² + C