No, the monopolist cannot sell more of a commodity at a higher price. This is because in the case of a monopoly, one firm constitutes the whole industry. Therefore, the entire demand of the consumers for a product faces the monopolist. Since the demand curve of the consumers for a product slopes downwards, the monopolist faces a downward sloping demand curve.
If he wants to increase the sale of his good, he must lower the price. He can raise the price if he is willing to sacrifice some sales.
