A. 67 B. 135 C. 75 D. 150

Trigonometry: If f(x)= 2sinx + cosx using exact values find f (120 degrees). if possible show steps.

Arada [10]

Answer: f(120°) = (√3) + 1/2

Step-by-step explanation:

i will solve it with notable relations, because using a calculator is cutting steps.

f(120°) = 2*sin(120°) + cos(120°)

=2*sin(90° + 30°) + cos(90° + 30°)

here we can use the relations

cos(a + b) = cos(a)*cos(b) - sin(a)*sin(b)

sin(a + b) = cos(a)*sin(b) + cos(b)*sin(a)

then we have

f(120°) = 2*( cos(90°)*sin(30°) + cos(30°)*sin(90°)) + cos(90°)*cos(30°) - sin(90°)*sin(30°)

and

cos(90°) = 0

sin(90°) = 1

cos(30°) = (√3)/2

sin(30°) = 1/2

We replace those values in the equation and get:

f(120°) = 2*( 0 + (√3)/2) + 0 + 1/2 = (√3) + 1/2

3 0

3 years ago

Write an equation for each linear function described. Show your work. The graph of the function passes through the point (2,1),

svp [43]

Step-by-step explanation:

As

The graph of the function passes through the point (2,1), and

y increases by 4 when x increases by 1.

so

x y

2 1

3 5

4 9

5 13

6 17

and so on

From the table:

$\mathrm{Slope\:between\:two\:points}:\quad \mathrm{Slope}=\frac{y_2-y_1}{x_2-x_1}$

$\left(x_1,\:y_1\right)=\left(2,\:1\right),\:\left(x_2,\:y_2\right)=\left(3,\:5\right)$

$m=\frac{5-1}{3-2}$

$m=4$

As the slope-intercept form of the line is

$y=mx+b$

putting m=4 and any point, let say (2, 1) to find y-intercept 'b'.

$1=\left(4\right)2+b$

$8+b=1$

$8+b-8=1-8$

$b=-7$

So putting $b=-7$ and $m=4$ in the slope-intercept form of the line

$y=\left(4\right)x+\left(-7\right)$

$y=4x-7$

Therefore, the equation for the linear function will be:

$y=4x-7$

8 0

2 years ago

Pls help me, its not hard

natulia [17]

Answer:

1. y = -x + 3

2. y = x - 3

3. y = 3x + 1

4. y = -3x - 3

Step-by-step explanation:

Hello! sorry, I just saw your message on the question I answered before asking for help so here you go, these are the answers, hope this helps.

Pls mark me brainliest if you can:)

3 0

3 years ago

Which products result in a perfect square trinomial? Select three options.

Kazeer [188]

Answer:

Second option: $(xy+x)(xy+x)$

Third option: $(2x-3)(-3+2x)$

Fifth option: $(4y^2+25)(25+4y^2)$

Step-by-step explanation:

By definition, a perfect square trinomial can be obtained by squaring binomials.

Then:

$(a+b)^2=(a+b)(a+b)=a^2+2ab+b^2\\\\(a-b)^2=(a-b)(a-b)=a^2-2ab+b^2$

Knowing this, to obtain a perfect square trinomial, the binomials that you multiply must be equals.

Therefore, the products result in a perfect square trinomial are:

$(xy+x)(xy+x)=(xy+x)^2=(xy)^2+2(xy)(x)+x^2=x^2y^2+2x^2y+x^2$

$(2x-3)(-3+2x)=(2x-3)^2=(2x)^2-2(2x)(3)+3^2=4x^2-12x+9$

$(4y^2+25)(25+4y^2)=(4y^2+25)^2=(4y^2)^2+2(4y^2)(25)+25^2=16y^4+200y^2+625$

8 0

3 years ago

Read 2 more answers

A student pushes a 51.5 kilogram bookshelf across a smooth floor with a net force of 67 N.

iren [92.7K]

The acceleration of the bookshelf is equal to 1.30 $m/s^2$

<u>Given the following data:</u>

Mass of bookshelf = 51.5 kilogram

Net force = 67 Newton

To determine the acceleration of the bookshelf, we would apply Newton's Second Law of Motion:

Newton's Second Law of Motion states that the acceleration of an object is directly proportional to the net force acting on the object while being inversely proportional to its mass.

Mathematically, Newton's Second Law of Motion is given by this formula;

$Acceleration = \frac{Net\;force}{Mass}$

Substituting the given parameters into the formula, we have;

$Acceleration = \frac{67}{51.5}$

Acceleration = 1.30 $m/s^2$

Read more on net force here: brainly.com/question/1121817

7 0

2 years ago