ПОМОГИТЕ ПОЖАЛУЙСТА ДОКАЗАТЬ ТОЖДЕСТВО. sin2α/1+cos2α=tgα

помогите пожалуйста ответить на вопросы 

1. Do you have a purpose in life? 2. Have you started thinking
about your future career? If yes, when? 3. What career
would you like to choose? 4. Who or what has been an influence
on you in choosing your future career? 5. Are you going to follow
in your parents’ footsteps? 6. Do you have a role model?
7. What qualifications are you going to get? 8. Are you going
to do any odd jobs to get some hands-on experience? 9. Do you
have a passion for something? 10. What skills do you have?
11. Are you a creative person? 12. Do you think you have got
the abilities to achieve your goals? 13. What are your
strengths? What are your weaknesses? 14. Have you done any
career assessment tests? 15. If your goals prove to be unachievable,
what are you going to do then?

найдите разницу между суммой ста четных натуральных чисел и первых ста нечетных натуральных чисел

Танк Т-34 движется со скоростью 30 м/с. Какой путь он пройдёт за 2 ч.