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3 years ago

Can anyone help me with trig identities?

Mathematics

1 answer:

nevsk [136]3 years ago

6 0

Answer:

cosA = √(21/25)

Step-by-step explanation:

We know

sin²(A) + cos²(A) = 1

Next, we know that sin(A) = 2/5. Plugging that into our equation, we get

(2/5)² + cos²A = 1

4/25 + cos²A = 1

subtract 4/25 from both sides to isolate cos²A

cos²A = 1 - 4/25 = 25/25-4/25 = 21/25

square root both sides to get

cosA = √(21/25)

We do not include -√(21/25) in our possible answer for cosA because this is in quadrant 1, so cosA must be positive.

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F(y) = y² + 10y + 21 <br>f'(2) = ? <br>

Ahat [919]

Answer:

Step-by-step explanation:

f'(2) = 2y + 10

f'(2) = 2(2) + 10

= 4 + 10

= 14

3 0

2 years ago

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Direction: Solve the given problems.

MAXImum [283]

<h2>○=> <u>Solution (6)</u> :</h2>

Ratio of two numbers = 2:3

The larger number = 6

Let the smaller number be x.

Which means :

$=\tt 2 : 3 \: = \: x : 6$

$= \tt \frac{2}{3} = \frac{x}{6}$

$=\tt 2 \times 6 = 3 \times x$

$=\tt 12 = 3x$

$=\tt x = \frac{12}{3}$

$\hookrightarrow\color{plum}\tt \: x = 4$

▪︎<u>Therefore, the smaller number = 4</u>

<h2>○=> <u>Solution (7)</u> :</h2>

36 compared to 6 = $\tt \frac{36}{6}$

Let the number be x.

Which means :

$= \tt \frac{36}{6} = \frac{x}{3}$

$=\tt \frac{36 \div 2}{6 \div 2} = \frac{x}{3}$

$=\tt \frac{36}{6} = \frac{18}{3}$

▪︎Therefore, the fractional number $\tt \frac{18}{3}$ is equal to $\tt \frac{36}{6}$ .

<h2>○=> <u>Solution (8)</u> :</h2>

Number of Rose's for 24 red Rose's = 6

This can be written in a ratio as 24:6

Number of roses = 8

Let the number of red roses for these roses be x.

Which means :

$=\tt \frac{24}{6} = \frac{x}{8}$

$=\tt 24 \times 8 = 6 \times x$

$=\tt 192 = 6x$

$=\tt x = \frac{192}{6}$

$\hookrightarrow \color{plum}\tt x = 32$

▪︎Therefore, 32 red roses are there if there are 8 roses.

<h2>○=> <u>Solution (9)</u> :</h2>

Number of children for 2 adults = 7

This can be written in a ratio as 7:2

Number of children in the plaza = 21

Let the number of adults be x.

Which means :

$= \tt \frac{7}{2} = \frac{21}{x}$

$=\tt7 \times x = 2 \times 21$

$=\tt 7x = 42$

$=\tt x = \frac{42}{7}$

$\hookrightarrow \color{plum}\tt \: x = 6$

▪︎Therefore, 6 adults were there in the plaza.

<h2>○=> <u>Solution (10)</u> :</h2>

Cost of 12 pencils = P60

Cost of 1 pencil :

$= \tt \frac{60}{12}$

$=\tt P5$

Thus, the cost of one pencil = P5

Cost of 25 pencils :

= Cost of one pencil × 25

$=\tt 5 \times 25$

$\color{plum}=\tt \: P \: 125$

▪︎Therefore, the cost of 25 pencils = P125

7 0

3 years ago

Someone please help me

exis [7]

V = 1/3 l h w

V = 1/3 (12)(15)(9)
V= = 540

answer 540 m^3

8 0

3 years ago

Translate the word statement to a numerical statement then solve the problem

nika2105 [10]

It might be 63 and 27 but if im wrong love me (plz dont really love me )

8 0

3 years ago

Read 2 more answers

Help please!<br> Sorry for the image quality.

VARVARA [1.3K]

Answer:

$\displaystyle (-1,\frac{-3}{2})$

General Formulas and Concepts:

<u>Pre-Algebra</u>

Order of Operations: BPEMDAS

Brackets
Parenthesis
Exponents
Multiplication
Division
Addition
Subtraction

Left to Right

<u>Algebra I</u>

Midpoint Formula: $\displaystyle (\frac{x_1+x_2}{2},\frac{y_1+y_2}{2})$

Step-by-step explanation:

<u>Step 1: Define</u>

<em>Find points from graph.</em>

Point (-3, 1)

Point (1, -4)

<u>Step 2: Find Midpoint</u>

Simply plug in your coordinates into the midpoint formula to find midpoint

Substitute [MF]: $\displaystyle (\frac{-3+1}{2},\frac{1-4}{2})$
[Fractions] Add/Subtract: $\displaystyle (\frac{-2}{2},\frac{-3}{2})$
[Fractions] Divide: $\displaystyle (-1,\frac{-3}{2})$

8 0

3 years ago