Answer:
θ = 2π/3 or 5π/3
Step-by-step explanation:
2 cosθ + 1= 0
when + 1 goes to R H S Side than it becomes negative by transposition method
2 cos = -1
now by dividing by 2 both sides we get
cosθ = -
since cosθ is negative
Cosθ = - cos 60°
it means either cosθ lies in 2nd or third quadrant
θ = π - π/3
or
θ = 2π- π/3
so θ = 2π/3 or 5π/3
We need to express this statement into a equation:
First of all. We will walk through the statement step by step into a mathematical language, so:
1. The sum of five and x:
x + 5
2. Twice the sum of five and x:
2(x + 5)
3. Eight less than x:
(x-8)
Finally the whole statement is:
4. <span>Twice the sum of five and x is eight less than x:
</span>
2(x + 5) = (x-8)
2x + 10 = x - 8
x = -18
Answer:
Step-by-step explanation:
Each successive year, he
earned a 5% raise. It means that the salary is increasing in geometric progression. The formula for determining the nth term of a geometric progression is expressed as
Tn = ar^(n - 1)
Where
a represents the first term of the sequence(amount earned in the first year).
r represents the common ratio.
n represents the number of terms(years).
From the information given,
a = $32,000
r = 1 + 5/100 = 1.05
n = 20 years
The amount earned in his 20th year, T20 is
T20 = 32000 × 1.05^(20 - 1)
T20 = 32000 × 1.05^(19)
T20 = $80862.4
To determine the his total
earnings over the 20-year period, we would apply the formula for determining the sum of n terms, Sn of a geometric sequence which is expressed as
Sn = (ar^n - 1)/(r - 1)
Therefore, the sum of the first 20 terms, S20 is
S20 = (32000 × 1.05^(20) - 1)/1.05 - 1
S20 = (32000 × 1.653)/0.05
S20 = $1057920