Answer:
x = pi/2 + 2 pi n x = pi + 2 pi n where n is an integer
x = 5pi /3 + 2 pi n
Step-by-step explanation:
8 cos^2 x + 4 cos x-4 = 0
Divide by 4
2 cos^2 x + cos x-1 = 0
Let u = cos x
2 u^2 +u -1 =0
Factor
(2u -1) ( u+1) = 0
Using the zero product property
2u-1 =0 u+1 =0
u = 1/2 u = -1
Substitute cosx for u
cos x = 1/2 cos x = -1
Take the inverse cos on each side
cos ^-1(cos x) = cos ^-1(1/2) cos ^-1( cos x) =cos ^-1( -1)
x = pi/2 + 2 pi n x = pi + 2 pi n where n is an integer
x = 5pi /3 + 2 pi n
Answer:
Option D.
Step-by-step explanation:
Let the coordinates of a point which divides the segment XY in the ratio of m : n is (x, y).
Segment X(-4, -9) and Y(4, 7) has been divided in the ratio of 2 : 6.
Therefore, x = ![\frac{[4m+n(-4)]}{m+n}=\frac{8-24}{2+6}](https://tex.z-dn.net/?f=%5Cfrac%7B%5B4m%2Bn%28-4%29%5D%7D%7Bm%2Bn%7D%3D%5Cfrac%7B8-24%7D%7B2%2B6%7D)
= -
= -2
and y = ![\frac{[7m+n(-9)]}{m+n}=\frac{14-54}{2+6}](https://tex.z-dn.net/?f=%5Cfrac%7B%5B7m%2Bn%28-9%29%5D%7D%7Bm%2Bn%7D%3D%5Cfrac%7B14-54%7D%7B2%2B6%7D)
= 
= -5
Therefore, the point (x, y) is (-2, -5).
Option D. will be the answer.
Answer:
7
Step-by-step explanation:
Simply subtract 6 from 13.
13-6=7
Hope this helps! :)
Answer:
Step-by-step explanation:
