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3 years ago

URGENT!!! Write the product as a sum or difference.

Mathematics

1 answer:

CaHeK987 [17]3 years ago

4 0

Answer:

3 sin(41t) - 3 sin(t)

Step-by-step explanation:

The general formula to convert the product of the form cos(a)sin(b) into sum is:

cos(a) sin(b) = 0.5 [ sin(a+b) - sin (a-b) ]

The given product is:

6 cos(21t) sin(20t) = 6 [ cos(21t) sin(20t) ]

Comparing the given product with general product mentioned above, we get:

a = 21t and b = 20t

Using these values in the formula we get:

6 cos(21t) sin(20t) = 6 x 0.5 [ sin(21t+20t) - sin(21t-20t)]

= 3 [sin(41t) - sin(t)]

= 3 sin(41t) - 3 sin(t)

Therefore, second option gives the correct answer

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Find all solutions for a triangle with c=70 c=24 and a=25

Slav-nsk [51]

Answer:

see the attachments for the two solutions

Step-by-step explanation:

When the given angle is opposite the shorter of the given sides, there will generally be two solutions. The exception is the case where the triangle is a right triangle (the ratio of the given sides is equal to the sine of the given angle). If the given angle is opposite the longer of the given sides, there is only one solution.

When a side and its opposite angle are given, as here, the law of sines can be used to solve the triangle(s). When the given angle is included between two given sides, the law of cosines can be used to solve the (one) triangle.

___

Here, the law of sines can be used to solve the triangle:

A = arcsin(a/c·sin(C)) = arcsin(25/24·sin(70°)) = 78.19° or 101.81°

B = 180° -70° -A = 31.81° or 8.19°

b = 24·sin(B)/sin(70°) = 13.46 or 3.64

5 0

3 years ago

Read 2 more answers

Write 75.854 in expanded form

mixer [17]

Answer:

70+5+.8+.05+.004

Step-by-step explanation:

8 0

3 years ago

Read 2 more answers

7. a hockey arena has 10 920 seats. the first row of seats around the rink has 220 seats. the number of seats in each subsequent

Mazyrski [523]

The number of rows in the arena is 26

<h3>How to determine the number of rows?</h3>

The hockey arena illustrates an arithmetic sequence, and it has the following parameters:

First term, a = 220
Sum of terms, Sn = 10920
Common difference, d = 16

The number of rows (i.e. the number of terms) is calculated using:

$S_n = \frac{n}{2}(2a + (n -1) * d)$

So,we have:

$10920 = \frac{n}{2}(2 * 220 + (n -1) * 16)$

Evaluate the terms and factors

$21840 = n(440 + 16n -16)$

Evaluate the like terms

21840 = n(424+ 16n)

Expand

21840 = 424n + 16n^2

Rewrite as:

16n^2 + 424n - 21840 = 0

Using a graphical tool, we have:

n = 26

Hence, the number of rows in the arena is 26

Read more about arithmetic sequence at:

brainly.com/question/6561461

#SPJ1

4 0

2 years ago

Suppose that a large mixing tank initially holds 100 gallons of water in which 50 pounds of salt have been dissolved. Another br

Serggg [28]

Answer:

dA/dt = 12 - 2A/(100 + t)

Step-by-step explanation:

The differential equation of this problem is;

dA/dt = R_in - R_out

Where;

R_in is the rate at which salt enters

R_out is the rate at which salt exits

R_in = (concentration of salt in inflow) × (input rate of brine)

We are given;

Concentration of salt in inflow = 4 lb/gal

Input rate of brine = 3 gal/min

Thus;

R_in = 4 × 3 = 12 lb/min

Due to the fact that solution is pumped out at a slower rate, thus it is accumulating at the rate of (3 - 2)gal/min = 1 gal/min

So, after t minutes, there will be (100 + t) gallons in the tank

Therefore;

R_out = (concentration of salt in outflow) × (output rate of brine)

R_out = [A(t)/(100 + t)]lb/gal × 2 gal/min

R_out = 2A(t)/(100 + t) lb/min

So, we substitute the values of R_in and R_out into the Differential equation to get;

dA/dt = 12 - 2A(t)/(100 + t)

Since we are to use A foe A(t), thus the Differential equation is now;

dA/dt = 12 - 2A/(100 + t)

5 0

3 years ago

1. Two sides of a right triangle are 8 and 12 in.

PtichkaEL [24]

I think it is 4
(12-8=4)

5 0

3 years ago