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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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Evaluate the function at the given numbers( correct to six decimal places). Use the results to guess the value of the limit or e

netineya [11]

Answer:

Value of the limit is 0.5.

Step-by-step explanation:

Given,

$F(x)=\frac{e^x-1-x}{x^2}$

When,

$x=1,F(1)=frac{e^1-1-1}{1}=e-2=0.718281$

$x=0.5, F(0.5)=\frac{e^0.5-1-0.5}{(0.5)^2}=0.594885$

$x=0.1, F(0.1)=\frac{e^0.1-1-0.1}{(0.1)^2}=0.517091$

$x=0.05, F(0.05)=\frac{e^0.05-1-0.05}{(0.05)^2}=0.508438$

$x=0.01, F(0.01)=\frac{e^0.01-1-0.01}{(0.01)^2}=0.501670 \hfill (1)$

Correct upto six decimal places.

Now,

$\lim_{x\to 0}F(x)=\lim_{x\to 0}\frac{e^x-1-x}{x^2}$ $(\frac{0}{0})$ form, applying L-Hospital rule that is differentiating numerator and denominator we get,

$\lim_{x\to 0}F(x)$

$=\lim_{x\to 0}\frac{e^x-1}{2x}$ $(\frac{0}{0})$ form.

$=\lim_{x\to 0}\frac{e^x}{2}=\frac{1}{2}=0.5\hfill (2)$

Limit exist and is 0.5. That is according to (1) we can see as the value of x lesser than 1 and tending to near 0, value of the function decreases respectively. And from (2) it shows ultimately it decreases and reach at 0.5, consider as limit point of F(x).

8 0

3 years ago

Normal Distribution quiz?

Leno4ka [110]

Area under ALL probability distribution curves is 1.0, because all possible outcomes are taken into account.

8 0

3 years ago

What is the sum of 1/4 and 1/5?

krok68 [10]

To add them, you first need a common denominator.
So multiply <span> 1/4 by 5/5 and 1/5 by 4/4 first.

Now they'll be 5/20 and 4/20.

Add them to get 9/20. </span>

3 0

3 years ago

Free points

elena-14-01-66 [18.8K]

Answer:

10932

2959

Step-by-step explanation:

5 0

3 years ago

Read 2 more answers

A circle with radius of 3cm sits inside a circle with radius of 11 cm? What is the area of the shaded region?

garri49 [273]

Answer:

3cm = 28.26

11cm = 379.94

3 x 3 x 3.14 = 28.26

11 x 11 x 3.14 = 379.94

hope this helps

8 0

4 years ago