Two Harmonic Waves Are Described By $y _ { 1 } = ( 6 \mathrm {~cm} ) \sin \left( \pi \left( \frac { 8 } { \mathrm {~m} } x + \frac { 2 } { \mathrm {~s} } t \right) \right)$

Multiple Choice

Two harmonic waves are described by $y _ { 1 } = ( 6 \mathrm {~cm} ) \sin \left( \pi \left( \frac { 8 } { \mathrm {~m} } x + \frac { 2 } { \mathrm {~s} } t \right) \right)$
$$y _ { 2 } = ( 6 \mathrm {~cm} ) \sin \left( \pi \left( \frac { 8 } { \mathrm {~m} } x - \frac { 2 } { \mathrm {~s} } t \right) \right)$$ From the choices given,determine the smallest positive value of x (in cm) corresponding to a node of the resultant standing wave.

A) 3
B) 0.25
C) 0
D) 6
E) 1.5