2cosx=2sin2x. Sin2x is an identity for 2sinxcos. So 2[2sinxcosx] gives you 4sinxcosx. 2cosx=4sinxcosx. Divide 2cosx on both sides and gives you 2sinx=0 and divide again, sinx=0. Sinx is 0 at 0 and 360 degrees, or pi and 2pi. So thats what x would be. 0,360,pi,2pi.
Answer:
n = 18
Step-by-step explanation:
(2n) and (n + 18) are vertically opposite angles and are congruent, then
2n = n + 18 ( subtract n from both sides )
n = 18
First, take off 4 feet of Stacy's rope, which is 19. (23-4=19). Then, divide 19 by 3. It should equal 6.3...
Answer:
He will save 21 dollars.
Step-by-step explanation:
44.99 - 23.99= 21
Answer:
For
, the group is CLOSED as it a polynomial.
Step-by-step explanation:
Here, the given polynomials are:

Now, a group G is said to be <u>CLOSED UNDER SUBTRACTION</u> if,
a and b are he elements of G ⇒ (a-b) is ALSO AN ELEMENT of G
Now, here:

or, 
Also, R(x) is a POLYNOMIAL.
So, R(x) is an Element of group G.
So, the set G of polynomials.
Hence, for the polynomial
, it will be a polynomial the group is CLOSED.