Final answer:
The best type of shampoo to use after a chemical relaxer is sulfate-free shampoo.
Step-by-step explanation:
After a chemical relaxer, it is best to use a sulfate-free shampoo. The chemical relaxer process can make the hair more fragile and prone to damage. Sulfate-free shampoos are gentler and less likely to strip the hair of its natural oils, making them a better choice for post-chemical relaxer care.