The cosine is correct, but it looks like you found $\displaystyle{\csc{{A}}}\usepackage{cmbright}\Huge\$ instead of $\displaystyle{\csc{{B}}}\usepackage{cmbright}\Huge\$ .

A and B are complementary angles, so their cofunctions are equal:

$\displaystyle{\cos{{B}}}={\sin{{A}}}\usepackage{cmbright}\Huge\$ and $\displaystyle{\csc{{B}}}={\sec{{A}}}\usepackage{cmbright}\Huge\$