Chứng minh rằng 1/ (sin x + cos x)^2 = 1+2sin x . cos x 2/ sin^4x + cos^4x = 1-2sin^2x . cos^2x 3/ sin^6x + cos^6x = 1-3sin^2x . cos^2x 4/ 1-sinx / cos x = cos x / 1+sin x giúp mình với nhaaaa

complex sentences from cach pair of sentences. Use the subordinator prov and make any necessary changes. 1. It might rain. Take an umbrella with you. (in case) 8. They were reading. Their mother was watching TV. (while) 9. He had checked every door. He went out today. (before)

Passive voice with two objects 1. Rachel will give you some advice. You ..................................................................................................................................................... Some advice ....................................................................................................................................... 2. I sent him a letter. ............................................................................................................................................................ ............................................................................................................................................................ 3. The police officer showed us the way. ............................................................................................................................................................ ............................................................................................................................................................ 4. Our neighbor gave me a lift. ............................................................................................................................................................ ............................................................................................................................................................ 5. She told me a lie. ............................................................................................................................................................ ............................................................................................................................................................ 6. They have written her a postcard. ............................................................................................................................................................ ............................................................................................................................................................ 7. Kerrie will make you a cup of tea. ............................................................................................................................................................ ............................................................................................................................................................ 8. The waiter has not brought us the coffee. ............................................................................................................................................................ ............................................................................................................................................................ 9. They did not offer her a seat. ............................................................................................................................................................ ............................................................................................................................................................ 10. We bought Betty a bit of butter. ............................................................................................................................................................ ............................................................................................................................................................

Mọi người giúp em câu này với ạ ! 2sin$^{3}$ ( x + $\frac{\pi}{2}$ ) + cos2x + cos ( $\frac{9\pi}{2}$ - x ) = 0

Hòa tan hết 4,6g Na vào cốc chứa 245,6g H2O thu được dd X Tính nồng độ mol và nồng độ % của dd X Biết Dx=1,25g/ml

cho $a+b\leq 1$. Tìm gtnn của $ab+\frac{1}{ab}$

Btvn¹: Tính bằng cách thuận tiện ($\frac{27}{25}$ - $\frac{4}{9}$) - ($\frac{2}{25}$ - $\frac{5}{9}$)

cho f{x}=x mũ 2- mx+15 a} tìm m để f{x}nhân 3 là 1 nghiệm b với vừa tìm được hãy tìm nghiệm còn lại của f {x}

Giải giúp em mấy bài này dc ko ạ😢😊😊

chứng minh rằng : ca dao thể hiện 1 cách sâu sắc tình yêu quê hương, gia đình của con người VN