Tìm `n`: `a)9.27^n=3^5` `b)(2^3:4).2^n=4` `c)3^(-2).3^4.3^n=3^7` `d)2^(-1).2^n+4.2^n=9.2^5`

Các câu hỏi liên quan

Grammar: Complete the text using the comparative or superlative form of the adjectives in brackets. There is an example at thebeginning (0). Ice cream is one of the (0) ___most popular __ (popular) desserts. But do you know about the journey of vanilla and chocolate ice cream, the world’s favourite flavours? It’s possibly the (1) ____________(long) journey of all your favourite foods. In Ancient Greece, people ate snow with honey. In Ancient China, there was a dessert with ice, too. Ice and snow, at 0°C, are (2) ____________ (cold) than ice cream, which is 0°C–2°C. This means that they were (3) ____________(bad) for people’s teeth.Teeth can break when we eat cold things, but the Greeks and Chinese possibly had (4) ____________ (strong) teeth than us. Was the Greek recipe (5) ____________(old) than the Chinese one? Nobody knows which one was first. What we do know is where modern ice cream comes from – France. The English had an (6) ____________ (early) recipe with milk. Later a man from Sicily put eggs and sugar in it too, in his café in Paris in the seventeenth century. This made the dessert (7) ____________(sweet). The ingredients travelled a long way, too. Vanilla and chocolate were both from Mexico.Chocolate was the (8) ____________(good) drink for men who went to fight against other villages. It was also (9) ____________ (hot) than modern hot chocolate and (10) ____________ (bitter) to drink, because there was no sugar. Sugar was originally from India. So when you have ice cream on your plate, you have a map in front of you! Enjoy it.