All categories

2 years ago

(1+sin y)(1+sin (-y))=cos^2 y)

Mathematics

2 answers:

Goryan [66]2 years ago

5 0

Sin (-x) = - sin x
sin^2+cos^2=1

(1+siny)(1-siny)=cos^2y
1-sin^2=cos^2y
cos^y=cos^2

Sloan [31]2 years ago

4 0

$(1+siny)(1+sin(-y))=cos^2y\\\\L=(1+siny)(1-siny)=1^2-sin^2y=1-sin^2y=cos^2y\\\\R=cos^2y\\\\L=R$

$sin(-x)=-sinx\\\\sin^2x+cos^2x=1\to1-sin^2x=cos^2x\\\\(a+b)(a-b)=a^2-b^2$

You might be interested in

Suppose an exponential function is fit to a set of data. Which of the following residual plots indicates that this function was

Zina [86]

The correct answer is the choice that you have selected, the third choice.

When, we are looking at the residuals for a regression line, we always want to see the points balance like in the third choice. This means that the equation that we found is right in the middle of the points.

7 0

2 years ago

Read 2 more answers

A department store sold 51 51 shirts one day. All short-sleeved shirts cost $14.00 $ 14.00 each and all long-sleeved shirts cost

Dmitrij [34]

Answer:

28 short-sleeved shirts were sold and 23 long-sleeved shirts were sold.

Step-by-step explanation:

We can solve this question by a system of equations.

I am going to say that:

x is the number of short-sleeved shirts sold.

y is the number of long-sleeved shirts sold.

A department store sold 51 shirts one day.

This means that $x + y = 51$

All short-sleeved shirts cost $14.00 each and all long-sleeved shirts cost $23.00 each. Total receipts for the day were $921.00.

This means that

$14x + 23y = 921$

How many of each kind of shirt were sold?

We have to solve the system of equations.

$x + y = 51$

$x = 51 - y$

--------------

$14x + 23y = 921$

$14(51 - y) + 23y = 921$

$714 - 14y + 23y = 921$

$9y = 207$

$y = \frac{207}{9}$

$y = 23$

--------

$x = 51 - y = 51 - 23 = 28$

28 short-sleeved shirts were sold and 23 long-sleeved shirts were sold.

7 0

3 years ago

How can you tell if a point is a solution to a system of equations?

Anna35 [415]

Answer: you have to substitute them into the equation

Step-by-step explanation:

example: x = 2y - 6

lets say you test 4/5 so it would be 4 = 2(5) - 6

this equals 4 = 10 - 6 which is true

so that is how you test to see if the equation is right

remember the first number goes to "x" and the second one goes to y

hope this helps mark me brainliest if you can

3 0

2 years ago

Traveling at a average speed of 50 miles per hour the trip from point a to be is 2 hours traveling at a speed of 20 miles per ho

dem82 [27]

What's your question..?

7 0

2 years ago

Which expressions are equivalent when m = 1 and m = 4?

s344n2d4d5 [400]

Answer:

expression 2

Step-by-step explanation:

<h2><u>Which expressions are equivalent when m = 1 and m = 4?</u></h2>

<h3><u>first expression:</u></h3>

5m -3 and 2m + 5 + m

when m = 1

5(1) - 3 = 2 and 2(1) + 5 + 1 = 8

and m = 4

5(4) -3 =23 and 2(4) + 5 + 4 = 17

<u>expression 1 IS</u><u> NOT EQUIVALENT</u><u> </u>

<h3><u>second expression :</u></h3>

3 m + 4 and m + 4 + 2 m

when m = 1

3 (1) + 4 = 7 and 1 + 4 +2 (1) = 7

and m = 4

3 (4) + 4 = 16 and 4 + 4 +2 (4) = 16

expression 2 <u>IS EQUIVALENT </u>

<h3><u>third expression :</u></h3>

2 m + 7 and 3 m - 3 + m

when m = 1

2(1) + 7 = 9 and 3(1) -3 + 1 = 1

and m = 4

2(4) + 7 = 15 and 3(4) -3 + 4 = 13

expression 3 IS <u>NOT EQUIVALENT</u>

<h3><u>fourth expression :</u></h3>

5 m + 3 and 4 m + 2 + 2 m

when m = 1

5(1)+ 3 = 8 and 4(1) + 2 +2(1) = 8

and m = 4

5(4)+ 3 = 23 and 4(4) + 2 +2(4) = 26

expression 4 is <u>NOT EQUIVALENT </u>

the expression that is <u><em>EXPRESSION 2 </em></u>

8 0

2 years ago

Read 2 more answers