This is the concept of algebra, to solve the expression we proceed as follows;
cos 2x-cosx=0
cos 2x=cosx
but:
cos 2x+1=2(cos^2x)
thereore;
from:
cos 2x=cos x
adding 1 on both sides we get:
cos 2x+1=cos x+1
2(cos^2x)=cosx+1
suppose;
cos x=a
thus;
2a^2=a+1
a^2-1/2a-1/2=0
solving the above quadratic we get:
a=-0.5 and a=1
when a=-0.5
cosx=-0.5
x=120=2/3π
when x=1
cos x=1
x=0
the answer is:
x=0 or x=2/3π
Answer:
b=15
Step-by-step explanation:
7(b+1)=2*56 (we cross multiply)
7b+7=112
7b=105
b=15
Hey there!
The answer is D. 1/5
An explanation is in the attached image below.
Hope this helps!
Answer:
Here's the simplest example possible: let's say x + y = 3 and x - y = 1. Solve the second equation for x by adding y to both sides: (x - y) + y = 1 + y. So x = 1 + y. Take that value of x, and substitute it into the first equation given above (x + y = 3).
Answer:
Exponents are done before addition, subtraction, multiplicaton, and division
Step-by-step explanation:
PEMDAS=
Parenthases
Exponents
Multiply
Divide
Add
Subtract