i^+k^\hat{\mathbf{i}}+\hat{\mathrm{k}}i^+k^
j^+k^\hat{j}+\hat{k}j^+k^
2i^+2j^2 \hat{i}+2 \hat{j}2i^+2j^
2i^+2k^2 \hat{\mathrm{i}}+2 \hat{\mathrm{k}}2i^+2k^