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2 years ago

Sammy wrote the following proof. What did he do wrong?

Mathematics

2 answers:

seraphim [82]2 years ago

8 0

i think it would be D i hope i helped

OLEGan [10]2 years ago

3 0

Answer:

Choice B is correct answer.

Step-by-step explanation:

We have given a expression.

cos²∅tan²∅

We have to simplify above expression.

Since, we know that

tan²∅ +1 = sec²∅

cos²∅tan²∅ = cos²∅(sec²∅-1)

cos²∅tan²∅ = cos²∅sec²∅-cos²∅

since, sec∅ is reciprocal of cos∅.

sec∅ = 1/cos∅

cos²∅tan²∅ = cos²∅(1/cos²∅)-cos²∅

cos²∅tan²∅ = 1-cos²∅

Since, from following equation;

cos²∅+sin²∅ = 1

cos²∅tan²∅ = sin²∅

Hence, choice B is the answer.

You might be interested in

Kelvin and Lewie each design surveys in order to determine the average number of people who buy food at the mall. Kelvin surveys

Lisa [10]

Answer:

Lewie Survey produces less valid result.

Step-by-step explanation:

Given:

1. Kelvin surveys every other person leaving the food area.

2. Lewie surveys every fifth person leaving the mall's main entrance.

Therefore,

Kelvin will able to produce valid result as he is surveying every person who is leaving food court.

Means,

There are high chances that would have bought food from the court.

Whereas,

Lewie is surveying every fifth person leaving the the mall's entrance.

Therefore,

Here probability to produce valid result is less as they may have not buy food or they may visited other shops.

So, Lewie survey will produce less valid result.

8 0

1 year ago

Read 2 more answers

I tell you these facts about a mystery number, $c$: $\bullet$ $1.5 < c < 2$ $\bullet$ $c$ can be written as a fraction wit

makkiz [27]

Answer:

Possible answer: $\displaystyle c = \frac{16}{10} = \frac{8}{5} = 1.6$ .

Step-by-step explanation:

Rewrite the bounds of $c$ as fractions:

The simplest fraction for $1.5$ is $\displaystyle \frac{3}{2}$ . Write the upper bound $2$ as a fraction with the same denominator:

$\displaystyle 2 = 2 \times 1 = 2 \times \frac{2}{2} = \frac{4}{2}$ .

Hence the range for $c$ would be:

$\displaystyle \frac{3}{2} < c < \frac{4}{2}$ .

If the denominator of $c$ is also $2$ , then the range for its numerator (call it $p$ ) would be $3 < p < 4$ . Apparently, no whole number could fit into this interval. The reason is that the interval is open, and the difference between the bounds is less than $2$ .

To solve this problem, consider scaling up the denominator. To make sure that the numerator of the bounds are still whole numbers, multiply both the numerator and the denominator by a whole number (for example, 2.)

$\displaystyle \frac{3}{2} = \frac{2 \times 3}{2 \times 2} = \frac{6}{4}$ .

$\displaystyle \frac{4}{2} = \frac{2\times 4}{2 \times 2} = \frac{8}{4}$ .

At this point, the difference between the numerators is now $2$ . That allows a number ( $7$ in this case) to fit between the bounds. However, $\displaystyle \frac{1}{c} = \frac{4}{7}$ can't be written as finite decimals.

Try multiplying the numerator and the denominator by a different number.

$\displaystyle \frac{3}{2} = \frac{3 \times 3}{3 \times 2} = \frac{9}{6}$ .

$\displaystyle \frac{4}{2} = \frac{3\times 4}{3 \times 2} = \frac{12}{6}$ .

$\displaystyle \frac{3}{2} = \frac{4 \times 3}{4 \times 2} = \frac{12}{8}$ .

$\displaystyle \frac{4}{2} = \frac{4\times 4}{4 \times 2} = \frac{16}{8}$ .

$\displaystyle \frac{3}{2} = \frac{5 \times 3}{5 \times 2} = \frac{15}{10}$ .

$\displaystyle \frac{4}{2} = \frac{5\times 4}{5 \times 2} = \frac{20}{10}$ .

It is important to note that some expressions for $c$ can be simplified. For example, $\displaystyle \frac{16}{10} = \frac{2 \times 8}{2 \times 5} = \frac{8}{5}$ because of the common factor $2$ .

Apparently $\displaystyle c = \frac{16}{10} = \frac{8}{5}$ works. $c = 1.6$ while $\displaystyle \frac{1}{c} = \frac{5}{8} = 0.625$ .

8 0

2 years ago

Read 2 more answers

Simplify the expression 3x(x – 12x) + 3x2 – 2(x – 2)2. Which statements are true about the process and simplified product? Check

olasank [31]

We have the expression:
3x(x-12x) + 3x^2 - 2(x-2)^2

First, we will expand the power 2 bracket as follows:
3x(x-12x) + 3x^2 - 2(x^2 - 4x +4)

Then, we will get rid of the brackets as follows:
3x^2 - 36x^2 + 3x^2 - 2x^2 + 8x - 8

Now, we will gather the like terms and add them as follows:
-32 x^2 + 8x - 8

We can take the 8 as a common factor:
8 ( -4x^2 + x -1)

3 0

1 year ago

The merry-go-round at the fair rotates 12 times each minute, and children are 15 feet from the center of the wheel when they are

castortr0y [4]

Answer:

i think c 21600pi

Step-by-step explanation:

5 0

2 years ago

Read 2 more answers

Daisy works at an ice-cream parlor. She is paid $10 per hour for the first 8 hours she works in a day. For every extra hour she

andre [41]

Answer:

80+(15x)

Step-by-step explanation:

10 times 8=80

1.5 times 10=15

so she gets 80 dollars for the first 8 hours then for every extra hour she gets 15 dollars

7 0

2 years ago