function of ema 21 34 90
Basically it is to see the trend direction simply, as long as it moves above the EMA it indicates the trend is still bullish.
As long as it moves below the EMA, it indicates the trend is bearish.
Of course this will make it easier for beginners to see the direction of the trend.

Seen in the example image below

If you have further questions, please write in the comments.
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