Answer:
[tex] {b}^{41} [/tex]
Step-by-step explanation:
1. Use power rule.
[tex] {b}^{21} ( {b}^{4} ) {}^{5} [/tex]
2. Use the power of rule again.
[tex] {b}^{21} {b}^{20} [/tex]
3. Use product rule.
[tex] {b}^{21} + 20[/tex]
4. simplify.
[tex] {b}^{41} [/tex]
Therefor, the answer is
[tex] {b}^{41} [/tex]
