1. | sin (kx) | dimensions of k = L^{-1} |

2. | 10^{kx} |
dimensions of k = L^{-1} |

3. | cot (kx^{2}/R) |
dimensions of k = L^{-1} |

4. | e ^{hf/kT} - 1 |
dimensions of k = M·L^{2}·T^{-2}·q^{-1} |

**NOTE:** In 4, k is the Boltzmann constant, which has a value
of 1.3 × 10^{-23} J/K.