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2 years ago

Evaluate the expression 7^2/ x^2 - 2 for x = 3

Mathematics

1 answer:

vovikov84 [41]2 years ago

4 0

Answer:

Step-by-step explanation:

7²/x²-2 when x=3

49/3²-2

49/9-2

49/7

answer=7

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Round 0.868 to the nearest tenth.

Anna11 [10]

Answer: 0.9

Step-by-step explanation:

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2 years ago

Read 2 more answers

<img src="https://tex.z-dn.net/?f=%5Cfrac%7B%5Csec%5Cleft%28x%5Cright%29%7D%7B%5Ccos%5Cleft%28x%5Cright%29%7D-%5Cfrac%7B%5Csin%5

DanielleElmas [232]

Answer:

Step-by-step explanation:

First, convert all the secants and cosecants to cosine and sine, respectively. Recall that $csc(x)=1/sin(x)$ and $sec(x)=1/cos(x)$ .

Thus:

$\frac{sec(x)}{cos(x)} -\frac{sin(x)}{csc(x)cos^2(x)}$

$=\frac{\frac{1}{cos(x)} }{cos(x)} -\frac{sin(x)}{\frac{1}{sin(x)}cos^2(x) }$

Let's do the first part first: (Recall how to divide fractions)

$\frac{\frac{1}{cos(x)} }{cos(x)}=\frac{1}{cos(x)} \cdot \frac{1}{cos(x)}=\frac{1}{cos^2(x)}$

For the second term:

$\frac{sin(x)}{\frac{cos^2(x)}{sin(x)} } =\frac{sin(x)}{1} \cdot\frac{sin(x)}{cos^2(x)}=\frac{sin^2(x)}{cos^2(x)}$

So, all together: (same denominator; combine terms)

$\frac{1}{cos^2(x)}-\frac{sin^2(x)}{cos^2(x)}=\frac{1-sin^2(x)}{cos^2(x)}$

Note the numerator; it can be derived from the Pythagorean Identity:

$sin^2(x)+cos^2(x)=1; cos^2(x)=1-sin^2(x)$

Thus, we can substitute the numerator:

$\frac{1-sin^2(x)}{cos^2(x)}=\frac{cos^2(x)}{cos^2(x)}=1$

Everything simplifies to 1.

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2 years ago

A bicycle company has designed and built a new model of sports bicycle. They have determined that the profit for the sale of the

ycow [4]

The answer would be c)$120

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2 years ago

Answers...............

umka21 [38]

Answer: Two acute angles

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2 years ago

Pleaseeeeeee helppppl asap

cluponka [151]

Answer:

Step-by-step explanation:

Let's use the rule GEMDAS (Grouping, Exponents, Multiply, Divide, Add, Subtract) from left to right. Therefore, we will simplify the equation in the parentheses. $2^{3} = 8. (1-8= -7)$ . -(-7) creates a double negative, deeming the 7 positive, because when there is two negatives the number will turn into a positive. $7^{2}$ = 49, -3 x 4= -12. Therefore the final form of the equation will be 49 - 12 = 37.

Let me know if there are mistakes.

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1 year ago