cos (2x) = cos x
2 cos^2 x -1 = cos x using the double angle formula
2 cos ^2 x -cos x -1 =0
factor
(2 cos x+1) ( cos x -1) = 0
using the zero product property
2 cos x+1 =0 cos x -1 =0
2 cos x = -1 cos x =1
cos x = -1/2 cos x=1
taking the arccos of each side
arccos cos x = arccos (-1/2) arccos cos x = arccos 1
x = 120 degrees x=-120 degrees x=0
remember you get 2 values ( 2nd and 3rd quadrant)
these are the principal values
now we need to add 360
x = 120+ 360n x=-120+ 360n x = 0 + 360n where n is an integer
Sorry don't know explane the question
Answer:
Answer:
£3692
Step-by-step explanation:
A = p(1 + r/n)^nt
Where,
A = future value
P = principal = £2350
r = interest rate = 4.2% = 0.042
n = number of periods = 1(annual)
t = time = 4 years
A = p(1 + r/n)^nt
= 2350(1 + 0.042/1)^1*4
= 2350(1 + 0.042)^4
= 2350(1.042)^4
= 2350(1.5789)
= 2770.42
A = £2770.42
Total years = 10
Remaining years = 10 – 4
= 6 years
Remaining 6 years
P = £2770.42
r = 4.9% = 0.049
n = 1
t = 6
A = p(1 + r/n)^nt
= 2770.42(1 + 0.049/1)^1*6
= 2770.42(1 + 0.049)^6
= 2770.42(1.049)^6
= 2770.42(1.3325)
= 3691.59
A = £3691.59
Approximately £3692
Thank you!
Answer:
6-2x+5+4x
Group the similar numbers
2x+11
Step-by-step explanation:
Tyler multiplied the numbers when he should've have grouped the similar numbers together
