# Trig identities:(

4,037 results

**Pre-Cal**

[Note: I'm still having issues with identities with regard to trig] Verify the Trig. identities: (a). cot(x+y)=(cotxcoty-1)/(cotx+coty) (b). sin0(cot0+tan0)=sec0 [Note: 0=theta symbol]

**Trig**

How do you express sin4x as a trigonometric funcition of x using the identities? I think that you are supposed to start with the sine sum identity and then use the double angle identities for sin2A and cos2A, but after that I get stuck...

**Precalculus**

How would you solve this trig function: cos2x=sin^2-2 how do you know what trig identities to use?

**trig**

TRIG Identities, Gr. 12: Prove: cot4x=1-tan^2x/2tan2x

**trig**

Let Q be an acute angle such that sinQ=.6. Find the values of the following using Trig Identities: cosQ and tanQ

**Trig**

Use Trig identities to verify that sec^4(x)-tan^4(x)=1+2tan^2(x), Only work with one side of the equation

**Trig**

Are any of these three problems identities? 1. Cos^2x-sin^2x=1-2sin^2x 2. Sinxsecx=cosxcscx 3. Sec^4x-tan^4/sec^2x=1+sin^2x If so, how can you conclude that any of them are identities?

**Trig**

Are any of these three problems identities? 1. Cos^2x-sin^2x=1-2sin^2x 2. Sinxsecx=cosxcscx 3. Sec^4x-tan^4/sec^2x=1+sin^2x If so, how can you conclude that any of them are identities?

**Trigonometry**

Use the trig Identities to find the other 5 trig functions. Problem 7.)Tan(90-x)=-3/8 8.)Csc x=-13/5 9.)Cot x=square root of 3 10.)Sin(90-x)=-.4563 11.)Sec(-x)=4 12.)Cos x=-.2351 I need HELP!

**Trig**

Im having serious issues with verifying Trig. identities. Please help! Here is an example: (tanX-secX)^2= 1-sinX/1+sinX

**trig**

Solving Trig Functions: How Do You Solve For Sin 7.5 Using Half-Angle and Double-Angle Identities?

**trig**

2sin(4x)[(cos(3/2)x)(cos(5x/2)-sin((15/4)x)]+x can someone simplify this using trig identities?

**Trig Identities**

Please help...I'm not understanding trig identities and how to manipulate and express these two problems in their associated functions. Thanks a)Express as a function of cos (theta) 2 sin^2(theta) - 1 b)Express as a function of sin (theta) or cos (theta) tan^2(theta) - 2 sec(...

**Trig identity.**

I need help with verifying these trig identities: 1) sin4x = 4sinxcos - 8sin^3 x cos x 2) cos3x = cos^3 x - 3sin^2 x cos x

**Trigonometry - Identities and proof**

Show that cot((x+y)/2) = - (sin x - sin y)/(cos x - cos y) for all values of x and y for which both sides are defined. I tried manipulating both sides in terms of trig identities but I don't really have a solution....help would be appreciated, thanks.

**Trig Identities**

Prove the following identities: 13. tan(x) + sec(x) = (cos(x)) / (1-sin(x)) *Sorry for any confusing parenthesis.* My work: I simplified the left side to a. ((sinx) / (cosx)) + (1 / cosx) , then b. (sinx + 1) / cosx = (cos(x)) / (1-sin(x)) I don't know how to verify the rest.

**Trig Identities **

secx - sinxtanx

**trig**

use trig identities to rewrite: (1/(1-cos4v))-(1/(1+cos4v))

**Trig identies, Calculus**

Use the identities cos^2 x + sin^2 x =1 and cos2x=cos^2 x -sin^2 x to show that cos^4 x -sin^4 x = cos2x Im not sure how, I can solve my problem with half angle identities but im not sure where to start with this.

**Trig**

What is sin^2 - cos^2 x/ 1-2cos^2 x, using the identities.

**trig**

what is the correct answer in trigonometric identities. DiViDE ; x^5 + 5x^4 - 2x^3 + 3x^2 + 2x + 1 by x + 3

**Trig**

Please help using identities (2tan30)/(1-tan^2 30)

**trig**

please help me. use trig. identities to find the exact value. tan 25° + tan 5° / 1- tan 25° tan 5°

**trig**

please help me. use trig. identities to find the exact value. tan 25° + tan 5° / 1- tan 25° tan 5°

**math**

how do i solve this using trig identities? 2 csc^2x = 3 cot^2x-1

**Trig Identities..**

Solve any way possibly? Thank you! 1-sin^2x/1-cosx

**Trig**

Two pilots take off from the same airport. Mason heads due south. Nancy heads 23 west of south. After 400 land miles, how far is Nancy from Mason’s route? I think 156.29, but I'm not sure because the question comes in a lesson on sum and difference identities, and ...

**Trig**

verify following trigonometric identities. 1/sec0tan0 = csc0 = sin0

**trig**

How do I prove these trig identities? secx-cosx/tanx =sinx And 1+sinx/cosx+ cox/ 1+sinx=2secx

**pre calculus 2**

use the fundamental trig. Identities to simplify tan^4x+2tan^2x+1

**identities trig?**

find all solutions to the equation in the interval [0,2pie] cos2x=cosx

**Trig Identities**

Proving identities: 1) 1+ 1/tan^2x = 1/sin^2x 2) 2sin^2 x-1 = sin^2x - cos^2x 3) 1/cosx - cosx = sin x tan x 4) sin x + tan x =tan x (1+cos x) 5) 1/1-sin^2x= 1+tan^2 x How in the world do I prove this...please help... I appreciateyour time thankyou soo much!!

**trig**

Evaluate giving exact values and identities. Calculator based solutions are not acceptable. Thanks for any help sin (-pi/12)

**Trig math**

how to split up using sum and difference identities cos (13pi/12) PLeaseeeeeeeeeee help!!! thanx a million

**Trig identities:(**

Sin4A - cos4A = sin2A - cos2A Can i just square root the left side??:O

**trig**

Evaluate giving exact values and identities. Calculator based solutions are not acceptable. Thanks for any help cos (7pi/12)

**trig**

Evaluate giving exact values and identities. Calculator based solutions are not acceptable. Thanks for any help cos (-5pi/12)

**trig**

using the trigonometric identities find the exact (radical form) value of cos (105 degrees)

**trig. identities**

sin2x+sin2y=2sin(x+y)cos(x-y) Please helpp mee!! thank you sooo much really!!

**trig**

I have to factor the expression and use fundamental identities: sins^2xcscx^2-sin^2x sec^4x-tan^4x

**trig**

Evaluate giving exact values and identities. Calculator based solutions are not acceptable. Thanks for any help cos (4pi/3 – 3pi/4)

**Trig**

We started a new lesson on Monday on identities. Our test is tommorrow. I have no idea of what I'm doing! Can somebody help me study?

**trig**

find all values of x on interval 0-2pi. (sin4x)(cos7x)=(cos4x)(sin7x) identities should be used.

**Trigonometry**

Solve. 2sin(2ƒÆ) + ã3 = 0 interval [0, 2ƒÎ) How do I start this? I feel like maybe Trig Identities, but I'm not really sure.

**Trig**

simplify the expression to a single term: (1-2Sin^2 X)^2 + 4sin^2 X Cos^2 X I'm not sure how to start this or which identities to use. Any suggestions?

**math-trig**

Use the double angle identities to find sin2x if sinx= 1/square of 17 and cosx<0 . Give exact answer.

**Trigonometry**

Simplify the expression using trig identities: 1. (sin4x - cos4x)/(sin2x -cos2x) 2. (sinx(cotx)+cosx)/(2cotx)

**Trig!**

The identities cos(a-b)=cos(a)cos(b)sin(a)sin(b) and sin(a-b)=sin(a)cos(b)-cos(a)sin(b) are occasionally useful. Justify them. One method is to use rotation matricies. Another method is to use the established identities for cos(a+b) and sin (a+b).

**math**

how would you find the angle to (3)^.5sin(2x)-2cos(2x)+2sin^2(x)=1 I know that you have to use the trig identities but then when i substitue the sin and cos(2x) in i don't know what to do. please help

**Math (trigonometry)**

Trigonometry identities are so hard... I need some help proving these identities: *Oh, and I'm only in grade 11, so the identities we use are quotient identity and Pythagorean identity. sinx/(sinx + cosx) = tanx/(1 + tanx) cos^2x - sin^2x = 2cos^2x - 1 Thanks! Lucy

**trig**

Use trigonometric identities to find sec theta, given that tan theta = Radical 5/ 3.

**trig identities**

Find the exact value of cos (2theta) given csc theta = 8/3 and 0 < theta < pi/2

**Trig**

Eight Fundamental Identities Sec thada - Cos thada How do I do this?

**trig**

How to get 5degree without using calculator using identities?

**Trig**

Use identities to find indicated values tan (theta)= (12/5), pi <0<3pi/2 Find sin (2theta)

**trig**

Use identities to find indicated values tan (theta)= (12/5), pi <0<3pi/2 Find sin (2theta)

**trig**

Given that tan B= 7/24 with B in quadrant III, find sin 2B, cos 2B, and tan 2B, using angle identities.

**Trig**

Use trigonometric identities to solve the equation csc^2x -(√3+1)cotx+(√3-1)=0 in the interval [0, 2pi]

**Trig identities**

Has a negative -5/13 Steve. If angles x and y are in the same quadrant and sin x =3/5 and cos y= -5/13 determine the value of sin (x-y)

**Pre-Calculus**

This question has me stuck. Use the Pythagorean identity sin^2 Θ + cos^2 Θ = 1 to derive the other Pythagorean identities, 1 + tan^2 Θ = sec^2 Θ and 1 + cot^2 Θ = csc^2 Θ. Discuss how to remember these identities and other fundamental identities.

**tRiG/ AlGeBrA**

1) Use double-angle identities to write the following expression, using trigonometric functions of x instead of 4x. cos 4x 2) Use half-angle identities to write the following expression, using trigonometric functions of x instead of x/4. sin x/4

**trig**

use sum or difference identities to find the exact value of the trigonometric function: tan 345 please show work, i cant figure out what im doing wrong!

**Trig identities**

Sin x/[1-cos(-x)] = csc x + cot x Please Verify the Identity. I have been going in circle with this one... Just a hint would be nice. Thank you.

**Pre-Cal (verifying trig identities)**

How would you verify the identity? sin^1/2x-cosx-sin^5/2xcosx=cos^3xradsinx

**trig**

1) Use double-angle identities to write the following expression, using trigonometric functions of x instead of 4x. cos 4x 2) Use half-angle identities to write the following expression, using trigonometric functions of x instead of x/4. sin x/4

**Trig Identities**

Explain why Sin of theta= -The square root of 1-cos^2 theta is not an identity, using either graphical or numerical reasoning.

**TRIG**

Verify the following identity. 1) sin(x+y) __________ = tanx+tany cosxcosy 2) Write cos3x in terms of cosx I cannot figure out how to solve for identities they are so hard. Any help appreciated!:)

**Trig**

Column 1 Column 2 (sin theta + cos theta)sq 1 + 2sin theta cos theta Question : how do you get column 1 to be the same as column 2?? using the trig identities

**Trig**

Proving Identities: 2 columns (tan + cot)^2 = sec^2 + csc^2 I'm having trouble breaking down the left side to = the right side.. Any help please

**trig**

in proving trigonometric identities if cot theta sin theta = cos theta. what is the correct answer?

**trig**

what is the correct answer in proving trigonometric identities if tan theta/sin theta = sec theta

**trig**

what is the correct answer in proving trigonometric identities if tan theta / sin theta = sec theta

**trig**

use basic identities to simplify the expression. csc θ cot θ / sec θ

**Trig Identities**

If tan(theta)=7/13 and cos(theta)<0, what is the exact value of sin(theta)?

**Trig Identities**

Why does cos^2(x)= 1/2cos(2x)+1/2? I am trying to integrate, but the answer key says to first rewrite the expression like the above. I don't get how to change cos^2(x) into that. Explain?

**Trig**

Half Angle Identities cosx = 7/25 greater than 270 deg and less than 360 Determine cos 1/2x a. -7rt2/10 b. 7rt2/5 c.7/25 d.-4/5 I get 7rt2/5 Is this correct??

**Math (Trig) a.s.a.p, thanks!**

verify the identities: 1.) 2tanx-(1+tanx)^2 = -secx 2.) cos(x-330degrees)=1/2(ã3cosx-sinx) *the ãis only over the 3* 3.) 1+cos2x/sinx=cotx any help is greatly appreciated!!

**Trig**

How do you express these problems as single trigonometric function values or as single numbers, using identities? 1. cos^2pi/8-1/2 2. tan34degrees/2(1-tan^2 34degrees) 3. 1/8sin29.5degreescos29.5degrees

**Trig**

How do you express these problems as single trigonometric function values or as single numbers, using identities? 1. cos^2pi/8-1/2 2. tan34degrees/2(1-tan^2 34degrees) 3. 1/8sin29.5degreescos29.5degrees

**math trig identities**

a)cos4x-sin4xcot2x=-1 b)1+sinx+cosx/1+sinx-cosx=cot(x/2) i tried to ask my teacher but she doesnt know please help me!

**trig**

in proving trigonometric identities if sec theta - tan theta sin theta is equal to cos theta. what is the correct answer?

**Trigonometric Identities**

Which of the following are trigonometric identities, I have narrowed it down to two - (cscx + cotx)^2 = 1 OR sin^2(x)sec^2(x) + 1 = cot^2(x)csc^2(x)

**trig identities**

cos94 degrees cos18 degrees+ sin94 degrees sin18 degrees. write the expression as the sine, cosine, or tangent of an angle.

**Trig **

Please help me to simplify using identities 1+tan^2x/tan^2x I don't really understand how to do please help

**trig**

How do you solve for these identities: 1-sin^2è/cosè= cosè sin^4è-cos^4è=2sin^2è-1

**Trig**

If sinx = 1/4 Find the exact value of cos2x I used the formula for double angle identities : cos2x = 1-2sin^2x and got the answer 1/2 The book says the answer is 7/8 How would they get to that conclusion?

**calculus**

need help simplifying some trig identities such as: (csc t) (sin t) cos t = 0.75 and tan t = 0.88, find sec t and cot t; (cot2t) (sin2t) + sin2 t; csc2t - cot2t/sin2t

**Social Studies**

"But assuming that national identities will persist, can a European identity be built alongside them or over them? Is there such an identity, and if not, is it desirable? Is there, or can there be, such a thing as European patriotism." Based on this excerpt, what is the main ...

**trig**

in proving trigonometric identities if 1 + sin^2 theta is equal to 2 sin^2 theta + cos^2 theta. what is the correct answer?

**trig**

Use standard identities to express sin(2θ+π/3) in terms of sinθ and cosθ

**trig**

what is the correct answer in proving trigonometric identities if tan theta cos^2 theta + cos^2 theta

**Trig/Precalc**

Find the greatest possible value of 5cos(x)+6sin(x). I know that it would be a good idea to look for identities that are in the form of acos(x)+bsin(x), but I can't seem to find any. Other than that I don't really know where to go with this problem. Any help would be much ...

**trig**

Use the fundamental identities to simplify the expression. cos^2θ/sin^2θ+cscθsinθ I got tan^2theta

**Trig**

How would you find tan80 and tan55 as needed in this problem? Use identities to find each exact value. (tan80+tan55)/(1-tan80tan55)

**Math**

Prove Trig. Identities 1. sec è (sec è - cos è)= tan^2 è 2. tan^2 è (1 + cot^2 è) = sec^2 è

**Trig**

Use reduction identities to determine if the following statement is true or false: tan (A-B) = tan (B-A) Is this starement True or False ?

**Trig**

Simplify each expression using fundamental identities. 1. Sin theta cot theta 2. 1-sin^2 theta / cos theta

**trig**

Work out the following identities a)sin pheta / cos pheta b)tan pheta cos pheta

**trig**

Work out the following identities a) sin theta/cos theta b) tan theta cos theta

**trig**

We are doing trig identities in school. I need help with these five: 1.1+sinx/1-sinx=cscx+1/cscx-1 2.tanx+sinx/1+cosx=tanx 3.sec^2x/sin^2x=1/sin^2x+1/cos^2x 4.tan^2x/1+tan^2x=1-cos^2x 5.sinx-sin^3x/cos^3x=tanx