welphygirl1299 welphygirl1299
  • 11-08-2017
  • Mathematics
contestada

What is the best first step if your plan is to find the exact value of cos 75°using the cosine angle sum identity?

Respuesta :

Аноним Аноним
  • 11-08-2017
cos 75  = cos (45 + 30)  = cos45 cos30 - sin45 sin30

=   1/ sqrt2 * sqrt3/2  - 1/ sqrt2 *  1/2

= sqrt3 / 2 sqrt2 - 1 / 2 sqrt2

=     sqrt3 - 1
     -------------
       2 sqrt2


Answer Link

Otras preguntas

The areas of the two watch faces have a ratio of 16:25. A=4(pie)cm^2 is the smaller watch face. What is the ratio of the smaller watch face to the radius of the
the popilation of Detroit, Michigan was 951,300 in. Detroit has been experiencing a population decile of 1.4% per year since 200. what is the projected populati
From "Loyalties." "Don't mind them." my father said. My mother called me from the back. "Go and collect our Nigerian goat," she said. Which type of humor does t
Suppose a certain religious university has a ratio of approximately 90 males to 110 females enrolled as students. If the current enrollment at the university i
stems grow away from gravity, and roots grow toward gravity. that describes what?
Help please!!?? Thanks
Jimmy is saving money to purchase a bicycle. The bike he wants costs $295 and he has already saved up forty dollars. Jimmy saves 25 dollars a month from his par
Please tell me facts about NAFTA
Y × 1.5 =20 what does Y equal
Find the quotient (35n 3 - 30n 2 + 25n) ÷ (-5n)