Yang is the positive force in the universe, and there is enormous yang and very weak yin (negative force) in the first, second, and third of the ninth trigrams. So the three yang are very positive.
三陽，卦爻之初九、九二、九三，陽氣盛極而陰衰微也。開泰，泰是卦名；乾上坤下，天地交而萬物通。