문제 1선택형dx\mathrm{d} xdχd\chidfgcxzsswedfgcxzssweϵσψηγ\epsilon\sigma\psi\eta\gammasdxcfdxdχdxdϰ\frac{sdxcfdx}{d\chi}\frac{\mathrm{d} x}{d\varkappa}
