Whoever answers 8-9 first correctly will get brainliest ! asap

Write a fraction less than 1, which has a denominator of 6 and is greater than 3/4 plz answer !

Aquadratic equation in standard from is written ax^2= bx+c, where a,b and c are real numbers and a is not zero?

Can someone me with #s 8, 9, and 11. with just one of the three also works. prove using only trig identities.