Question

find a quadratic equation whose roots are sin 15 and cos 15

sir, sorry but I didn't understand 6 th question

• tan x = -1 for 0<x<2π ?????? 
  

loan taken from drectors entry in tally

1.2+2.3+3.4+...+n(n+1)=n(n+1)(n+2)/3

A chord10 cm long is drawn whose radius is 5root2 cm. find the area of both segments?

What is the differentiation of cot x using 1st principle 

prove that how pie is a irrational number.