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2 years ago

Complete the identity. cos (alpha - beta)/cos alpha cos beta = ?

2 answers:

5 0

$\frac{cos(a-b)}{cos(a)cos(b)} = \frac{cos(a)cos(b)+sin(a)sin(b)}{cos(a)cos(b)} = 1+ \frac{sin(a)sin(b)}{cos(a)cos(b)} =1+tan(a)tan(b)$

Note that I used these identities : $cos(a-b)=cos(a)cos(b)+sin(a)sin(b)$ and $tan(a)= \frac{sin(a)}{cos(a)}$

MrRa [10]2 years ago

3 0

I belive the answer to be b

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A ball is thrown from an initial height of 3 feet with an initial upward velocity of 28 ft/s. The ball's height h (in feet) afte

dimaraw [331]

The value of t at a height of 11 feet is 0.36 sec when the ball is going upwards and 1.39 seconds when the ball is coming downwards.

<h3>What is a quadratic equation?</h3>

A quadratic equation is an equation whose leading coefficient is of second degree also the equation has only one unknown while it has 3 unknown numbers.

It is written in the form of ax²+bx+c.

Given that the height of the ball at time t is given by the function,

$h(t) = 3+ 28t -16t^2$

where t is in seconds and h is in feet.

Now, the height of the ball is given to be 11 feet, therefore, substituting the value of h in the function as 11,

$h(t) = 3+ 28t -16t^2\\\\11 = 3+ 28t -16t^2\\\\-16t^2 + 28t +3 -11 = 0\\\\-16t^2 + 28t -8 = 0$

Now, solving the given quadratic equation, we will get,

$x= \dfrac{-b\pm \sqrt{b^2-4ac}}{2a}\\\\t = \dfrac{-(28)\pm \sqrt{(28)^2-4(-16)(-8)}}{2(-16)}\\\\t= 0.36\ or\ 1.39$

Hence, the value of t at a height of 11 feet is 0.36 sec when the ball is going upwards and 1.39 seconds when the ball is coming downwards.

Learn more about Quadratic Equations:

brainly.com/question/2263981

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7 0

1 year ago

Part a: identity a fraction equivalent to 15/60. show all work.

Sliva [168]

Answer:

15/60

First divide by 3 to each

5/20

Now divide by 5 to each

1/4

8 0

2 years ago

Read 2 more answers

The nth term of a sequence is 25-3n

Komok [63]

Answer:

22, 19, 16 and - 5

Step-by-step explanation:

To evaluate any term from the n th term formula substitute the terms position value for n

given $a_{n}$ = 25 - 3n, then

(a)

$a_{1}$ = 25 - (3 × 1) = 25 - 3 = 22

$a_{2}$ = 25 - (3 × 2) = 25 - 6 = 19

$a_{3}$ = 25 - (3 × 3) = 25 - 9 = 16

(b)

$a_{10}$ = 25 - (3 × 10) = 25 - 30 = - 5

5 0

2 years ago

Read 2 more answers

A salesperson earns $450.20 per week plus 15% of her weekly sales. Which of the following describes the sales necessary for the

lapo4ka [179]

First we must construct an equation to model the problem. (In this case we will use an inequality instead) This is what I came up with:
450.20+0.15s>=600.10

This equation shows how if her base earnings ($450.20) are added to 15% of her sales, represented by s, then the total will be greater than or equal to $600.10
Next, we simply solve for s. (steps shown below)

1) 450.20+0.15s>=600.10 (simply restating the inequality)
2) 0.15s>=149.90 (here I isolated the variable)
3)0.15s/0.15>=149.90/0.15 (Finally I solve for s by dividing both sides by 0.15, this will isolate s on the left and leave the answer on the right)
4) s>=999.33... (here I found the total sales the salesperson would need to reach his/her goal of earning a minimum of $600.10; the 3's after the decimal are repeating so in the next step I will round up to the nearest hundredth (b/c this is what money is rounded to and if I round down he/she would make less than her goal. This means i must round up.))
5) s>=999.34 (simple rounding; once again I rounded up b/c rounding down would slightly bring the total earnings to less than the goal)

<u>Therefore, the salesperson would need his/her sales to be $999.34 in order for his/her total earnings for the week to be at least $600.10</u> (greater than or equal to $600.10)

<u>Hope this helped!</u>

4 0

3 years ago

Y’all I need to ask a question.

Gnesinka [82]

Answer:

A bank normally is the organization which lends money

Step-by-step explanation:

5 0

2 years ago