⚠ (\partial)/(\partial x)(7xsin(y-z)) is read as dif(7x*sin(y-z),x): use * for multiplication, use ^ for a power, use dif(expression, variable) for a derivative with respect to that variable, use (numerator)/(denominator) for a quotient

Differentiate with respect to x while holding y, z constant

Let's differentiate: $\frac{\mathrm{\partial }}{\mathrm{\partial }x}(7x·\sin (y-z))$

$7·\sin (y-z)·\frac{\mathrm{d}}{\mathrm{d}x}\left(x\right)$

$7·\sin (y-z)·1$

▶Derivative:   $7·\sin (y-z)$