It is formed as- take a paper and draw angle of 90 degrees on it. fold paper on both arms of angle to form a crease. suppose the basea arm as i unit. take a compass and draw a arch cutting perpendicular. join ending point of base arm and point where it cut the perpendicular and make a crease. then again make a perpendicular on hypo. of that angle. do it further till oyu get the number to which you want to represent.
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