Answer:
see explanation
Step-by-step explanation:
Using the double angle identity for sine
sin2x = 2sinxcosx
Consider left side
cos20°cos40°cos80°
= 
(2sin20°cos20°)cos40°cos80°
= 
(2sin40°cos40°)cos80°
= (sin80°cos80° )
= 
(2sin80°cos80° )
= . sin160°
= . sin(180 - 20)°
= . sin20°
= 
= right side , thus proven
Answer:
median
Step-by-step explanation:
The first step is to sort the numbers from largest to smallest (you could go the other way as well).
60 52 48 44 20 16 12
The median is the middle number 44 in this case. The median has 3 numbers on its left and 3 on its right (in this case). 44 has 60 52 48 or its left and 20 16 and 12 on its right.
The mean is the average. We'll call it the new average
The mean is 60 + 52 + 48 + 44 + 20 + 16 + 12 = 252
The new mean is 252 / 7 = 36
=====================
The old median is the average between the middle 2 numbers (before you added 60 you had 6 numbers)
52 + 48 + 44 + 20 + 16 + 12 = the average of 44 + 20 which 64/2 = 32
The old mean was (52 + 48 + 44 + 20 + 16 + 12)/6 = 32.
=======================
The median increased from 44 to 32 = 12
The mean went from 32 to 36 which is 4
Answer: the median increased more
Answer:
3.9375
Step-by-step explanation:
Answer:
Answer is 225.
We have to find the sum of 15 terms of the series
sigma 1 to 15 (2n-1)
This can be split as per summation terms as
sigma 2n - sigma 1
sigma 2n can again be simplified by taking 2 outside
sigma 2n= 2 times sum of natural numbers of 1 to 15
= 2(15)(16)/2= 240
sigma 1= 1+1+...15 times= 15
Hence final answer is
= 2 times sigma n - (n) = 240-15 = 225.
Step-by-step explanation:
Answer:
D
Step-by-step explanation:
2 sin²x=sin x
2 sin² x-sin x=0
sin x(2 sin x-1)=0
sin x=0
x=0,π
2 sin x-1=0
2 sin x=1
sin x=1/2= sin π/6,sin (π-π/6)
x=π/6,5π/6
