cos4x = cos2x
We know that:
cos2x = 1-2cos^2 x
==> cos4x = 1-2cos^2 (2x)
Now substitute:
==> 1-2cos^2 (2x) = cos2x
==> 2cos^2 (2x) + cos2x - 1 = 0
Now factor:
==> (2cos2x -1)(cos2x + 1) = 0
==> 2cos2x -1 = 0 ==> cos2x =1/2 ==> 2x= pi/3
==> x1= pi/6 , 7pi/6
==> x1= pi/6 + 2npi
==> x2= 7pi/6 + 2npi
==> cos2x = -1 ==> 2x= pi ==> x3 = pi/2 + 2npi.
<span>==> x= { pi/6+2npi, 7pi/6+2npi, pi/2+2npi}</span>
Answer:
The answer to your question is There were sold 166 adult tickets and 294
children tickets.
Step-by-step explanation:
Data
Total number of seats = 460
cost for adults = a = $52
cost for children = c = $26
Total cost = $16276
Process
1.- Write equations to solve this problem
a + c = 460 Equation l
52a + 26c = 16276 Equation ll
2.- Solve the system of equation by substitution.
-Solve equation l for a
a = 460 - c
-Substitute a in equation ll
52(460 - c) + 26c = 16276
-Expand
23920 - 52c + 26c = 16276
-Simplify
-26c = 16276 - 23920
-26c = -7644
c= -7644/-26
c = 294
3.- Find a
a = 460 - 294
a = 166
7-(p+t) = 9(85-n) = 7(4+y)
Algebra is a kind of mathematics that includes symbols and the arithmetic operations across these symbols. These symbols do not have any fixed values and are called variables.
An algebra expression contain coefficient variable and a constant
We apply various methods to solve those question
An algebra expression is also called an equation
let the number be x
Seven less than the of p and t
= 7-(p+t)…….(1)
Nine times a number y subtracted from 85
= 9(85-n)…..(2)
Seven times the sum of four and y
= 7(4+y)……(3)
Combining equations (1), (2) and (3) according to the question :
7-(p+t) = 9(85-n) = 7(4+y)
Learn about algebra here :
brainly.com/question/2972832
#SPJ9
Answer:
Step-by-step explanation:
Three feet make a yard, so 2 yards is 6 feet
If we divide the top (numerator) and the bottom (denominator) by 2 we get
÷ 
=
<h3>
Answer: x = 4</h3>
==================================================
Explanation:
Replace f(x) with 0 and solve for x.
f(x) = 3x-12
0 = 3x-12
3x-12 = 0
3x = 12
x = 12/3
x = 4 is a zero, aka root, of the function
---------------
Check:
f(x) = 3x-12
f(4) = 3(4)-12
f(4) = 12-12
f(4) = 0
The answer is confirmed.
