oblicz:a) 2 sin45°- tg²60° b)sin²60°+cos²60° c)tg30°x ctg30°-cos²45° przyjmujemy ze (sin α)²=sin²α, (cos α)²=cos² α, (tg α)²=tg² α (α=alfa)

a) 2 sin45°- tg²60° = 2*(√2):2 - (√3)² = √2 -3 b)sin²60°+cos²60° = (√3:2)² + (½)² = ¾ +¼ = 1 c)tg30°x ctg30°-cos²45° = (√3):3 *√3 - (√2:2)² = ⅓ - (2/4) = ⅓ - ½ = 2/6 -3//6 = -1/6