Which wave would produce a standing wave when combined with the original one

When original wave superimpose with its own reflected wave travelling in opposite direction then it will produce standing wave

Explanation:

Let say the equation of original wave is

now the equation of its reflected wave which is reflected 100% is given as

now by superposition of above two waves we will have

so above shows the equation of standing wave

so we can say that When original wave superimpose with its own reflected wave travelling in opposite direction then it will produce standing wave