Answer: 
Step-by-step explanation:
First way
arcsin(1/4) means that 1/4 sin of the angle.
sin(α)=1/4
sin²α+cos²α=1
(1/4)²+cos²α=1
cos²α=1-1/16 =15/16
cosα=+/-(√15)/4
<span>Second way
</span>
sin(α)=1/4 =opposite leg/hipotenuse
cos(α)=adjacent leg/hypothenuse
adjacent leg =√(hypotenuse²- Opposite²)=√(16-1)=√15
cosα=+/-√15/4
For one value of sinα, possible 2 values of cosα.
Answer:
Step-by-step explanation:
Half life is the time taken by a radioactive substance to reduce of half of its original size
If the half life of radium is 1600, this means that the original radioactive substance N0 have reduced to N0/2 after 1600 years
if we are given N0 = 1000grams
The amount of the substance that will remain after 1600 years will be N0/2 i.e 1000/2 = 500g
<em>Hence 500 grams of radium will be left after 600years</em>
Answer:
After 7.40 years it will be worth less than 21500
Step-by-step explanation:
This problem is solved using a compound interest function.
This function has the following formula:
Where:
P is the initial price = $ 34,000
n is the depreciation rate = 0.06
t is the elapsed time
The equation that models this situation is:
Now we want to know after how many years the car is worth less than $ 21500.
Then we do y = $ 21,500. and we clear t.
After 7.40 years it will be worth less than 21500
