Ask question

Ask question

All categories

3 years ago

12

Select all the true sentences!!!

1 answer:

iragen [17]3 years ago

6 0

Answer:

the second one and third one

Step-by-step explanation:

You might be interested in

Evalute costheta if sintheta = (sqrt5)/3

torisob [31]

Answer:

$\large\boxed{\cos\theta=\pm\dfrac{2}{3}}$

Step-by-step explanation:

Use $\sin^2x+\cos^2x=1$ .

We have

$\sin\theta=\dfrac{\sqrt5}{3}$

Substitute:

$\left(\dfrac{\sqrt5}{3}\right)^2+\cos^2\theta=1\qquad\text{use}\ \left(\dfrac{a}{b}\right)^n=\dfrac{a^n}{b^n}\\\\\dfrac{(\sqrt5)^2}{3^2}+\cos^2\theta=1\qquad\text{use}\ (\sqrt{a})^2=a\\\\\dfrac{5}{9}+\cos^2\theta=1\qquad\text{subtract}\ \dfrac{5}{9}\ \text{from both sides}\\\\\cos^2\theta=\dfrac{9}{9}-\dfrac{5}{9}\\\\\cos^2\theta=\dfrac{4}{9}\to \cos\theta=\pm\sqrt{\dfrac{4}{9}}\\\\\cos\theta=\pm\dfrac{\sqrt4}{\sqrt9}\\\\\cos\theta=\pm\dfrac{2}{3}$

3 0

3 years ago

Read 2 more answers

Six students earned a perfect score on a history quiz. Only 5% of the entire grade earned a perfect score. How many students are

stiks02 [169]

Answer:

120

Step-by-step explanation:

If 6 = 5%, then 6 = 1/20 of the total grade. 6×20= 120

5 0

3 years ago

Determine if a triangle can be formed with the given lengths. If it can, classify it as acute,

lisabon 2012 [21]

Answer:

steps below

Step-by-step explanation:

1. It can be formed a triangle: sum of any two sides is greater than the 3rd side

2. It can't be an obtuse triangle: 5² + 7² = 74 < 10²

the triangle is an obtuse-angled triangle if the square of the longest side (c²) is greater than the sum of the square of other two sides (c²>a²+b²)

6 0

3 years ago

Adding and Subtracting Complex Numbers.<br><br> Add.<br><br> (-3+3i)+(-6+6i)

Arisa [49]

<span>(-3 + 3i) + (-6 + 6i) =

= -3 + 3i + (-6) + 6i

= 3i + 6i + (-3) + (-6)

= 9i + (-9)

= 9i - 9
</span>

4 0

3 years ago

Two functions f and g are defined on the set R, of real numbers by f : x  2x  3 and

iren2701 [21]

Answer:8

Step-by-step explanation:

3 0

3 years ago