1answer.
Ask question
Login Signup
Ask question
All categories
  • English
  • Mathematics
  • Social Studies
  • Business
  • History
  • Health
  • Geography
  • Biology
  • Physics
  • Chemistry
  • Computers and Technology
  • Arts
  • World Languages
  • Spanish
  • French
  • German
  • Advanced Placement (AP)
  • SAT
  • Medicine
  • Law
  • Engineering
beks73 [17]
3 years ago
10

In exercises 5 and 7, tell whether or not f(x) = sin x is an identity.

Mathematics
1 answer:
Dmitry [639]3 years ago
7 0
For 5, we can make 1/csc x = sinx, but we're then left with sin^2+cos^2x(sinx)=sin(sin+cos^2x), which doesn't give us anything. False.

For 7, we know that cosx= tanx/sinx and cotx=1/tanx, so we cross out the tan x's and get 1/sinx, which is not sinx. False

15 - (1-cos^2u)/cos^2u=tan^2u, turn 1-cos^2u=sin^2u and square root both sides to get sin/cos=tan

17 - tanx = sinx/cosx, so multiply that with sinx on the right to get sin^2x/cosx, and multiply both sides by cosx to get cos^2x-1=sin^2x (assuming that (cos^2x-1)/cosx is what was meant on the right)

23 - don't know how to prove that true, sorry

31  -  (cos^4x-sin^4x)=(cosx+sinx)(cosx-sinx)(cos^2x+sin^2x)=(cosx+sinx)(cosx-sinx)=cos^2x-sin^2x
You might be interested in
What is the product of
nydimaria [60]
\frac{10}{ m^{5} }
3 0
3 years ago
Please help me!! <br> solve 31 = x + 25.5
serious [3.7K]

Answer:

x = 5.5

General Formulas and Concepts:

<u>Pre-Algebra</u>

  • Equality Properties

Step-by-step explanation:

<u>Step 1: Define</u>

31 = x + 25.5

<u>Step 2: Solve for </u><em><u>x</u></em>

  1. Subtract 25.5 on both sides:                    5.5 = x
  2. Rewrite:                                                      x = 5.5
6 0
2 years ago
Read 2 more answers
Isaac is working as a security guard. He earns $8.45 an hour. He earns double time for any overtime over 40 hours. Last week he
andreev551 [17]

Answer:

$405.60

Step-by-step explanation:

If Isaac works for 40 hours will earn $8.45×40=$388. Since he worked 4 extra hours, he will earn $8.45×2×4 since he worked 4 extra hours. $8.45×2=$16.90, which is the amount he earns for every extra hour he works. $16.90×4=$67.60. Now if we add $67.60+$388=$405.60.

Hope this helps!

6 0
3 years ago
BRAINLIST
marissa [1.9K]
It’s b
Z+23=41
Because you don’t know what z is
7 0
3 years ago
I need the smaller and larger angle
SSSSS [86.1K]

Answer:

x=11

Step-by-step explanation:

(4x)+(3x+13)=90                

if you look at the beam, it includes a 90 degree angle.

7x+13=90

distributive property

7x=77

subtracted both sides by 13

x=11

divided both sides by 7 to isolate x

4(11)         3(11)+13

44             33+13

                36

4(x) is the larger angle

6 0
3 years ago
Other questions:
  • -|8|—|11-8| complute the value of the given expression
    15·1 answer
  • The moon was about 240,000 miles from earth. What is the distance written as a whole number by a power of ten?
    14·1 answer
  • If m and n vary directly and m=3 when n=2, what is the value of m when n=4<br> no
    10·1 answer
  • The bumper car ride at the state fair has 2 red cars, 4 green cars, an for the ride and is assigned a the probability that both
    10·1 answer
  • 4y+5+3y= what...?please help me ​
    5·1 answer
  • PLEASE HELP ASAP!!!!
    10·2 answers
  • Will mark brainliest and rate 5/5<br> 20 POINTS WILL BE GIVEN
    5·2 answers
  • Mr. Zhāng received a shipment that
    5·2 answers
  • (10 POINTS) Rectangle ABCD is dilated with center at (0, 0) and scale factor 2. Select the three statements that are true about
    14·1 answer
  • Write the factor tree of 20​
    12·1 answer
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!