Please help me on this. 1 ) prove that h²(cot² α - cot² β) = 2α²

2 ) if α=20°, β=30°, AC=360m, find height PQ

(please help me on this and I beg for proper answers pls, spent almost 3 hours on this)​

Alina fully simplifies this polynomial and then writes it in standard form. xy2 – 2x2y + 3y3 – 6x2y + 4xy2 if alina wrote the last term as 3y3, which must be the first term of her polynomial in standard form? xy2 5xy2 –8x2y –2x2y