AlexThadunny AlexThadunny

21-11-2016
Mathematics

contestada

if cos2X=1/3 and 0<=2X<=pi, find cosX ...?

Respuesta :

HomertheGenius HomertheGenius

24-11-2016

cos 2 X = 1/3
cos 2 X = cos ² X - sin² X
cos ² X - sin ² X = 1/3
+
cos ² X + sin ² X = 1
------------------------------
2 cos ² X = 4/3 / : 2
cos ² X = 2/3
cos X = √2/3 ( angle X is in the 1st quadrant )

Answer Link

Otras preguntas

Simplify the expression 7v + 2w-12v

Why can't you change the subscripts in a formula in order to balance a chemical equation?

The area of a triangle is 6.75 m to the 2 power. If the base of the triangle is 3 m, what is the height of the triangle?

simplify the expression 4-3(2+5v)+7

Solve for " x " --- 20/x = 4/9 ? explain. (:

How to show your work to solve 3r^2-16r-7=5

a retailer buys a shirt in bulk at a unit price of $18. the shirt is marked up 36%to sell in the store. what is the price of the shirt in the store

After sales tax is added the total cost of a $58 purchase $61.48 what is the sales tax rate on the purchase?

What's an equivalent ratio to 12:10 ? ( explain also too please! :D )

What's an equivalent ratio to 12:10 ? ( explain also too please! :D )