This discussion is now closed.

Check out other Related discussions

- The Directrix of a Parabola
- Quatum Mechanics Primer Isaac Physics
- btec science unit 7 part a release 2023 january
- ART GCSE celebration
- Ocr law alevel h418
- Last minute research project!!! Help
- Macbeth gcse/igcse help + annotations
- Help urgent computer science
- macbeth gcse igcse annotations and help
- inspector calls revision help gcse
- CB1/CB2/CB3/CB9 exam
- cb1,cb2,cb3, cb9 exam gcse edexcel bio
- Help on choosing an epq
- CB1/CB2/CB3/CB9 exam Edexcel GCSE
- Cas shield login request
- sociology gcse
- IGCSE English language B ❤️😭 23 May 2023
- Help me graduate pls 😭| Survey for my final year project
- Gcse english revision
- Gcse results

yo all..

just wondering if you can help me with this

Sin4X + Sin2X = 0

i used the sum and product formula to get

2Sin3XCosX = 0

then im stuck

can someone help me out?

just wondering if you can help me with this

Sin4X + Sin2X = 0

i used the sum and product formula to get

2Sin3XCosX = 0

then im stuck

can someone help me out?

MalaysianDude

yo all..

just wondering if you can help me with this

Sin4X + Sin2X = 0

i used the sum and product formula to get

2Sin3XCosX = 0

then im stuck

can someone help me out?

just wondering if you can help me with this

Sin4X + Sin2X = 0

i used the sum and product formula to get

2Sin3XCosX = 0

then im stuck

can someone help me out?

The easiest approach is:

sin 4x = - sin 2x

2 sin 2x cos 2x = - sin 2x

sin(2x) (1+2cos(2x)) = 0.

So sin(2x) = 0 => x = 0, 90, 180, etc.

Or cos(2x) = -1/2. => x = 60, 120, etc

theone

The easiest approach is:

sin 4x = - sin 2x

2 sin 2x cos 2x = - sin 2x

sin(2x) (1+2cos(2x)) = 0.

So sin(2x) = 0 => x = 0, 90, 180, etc.

Or cos(2x) = -1/2. => x = 60, 120, etc

sin 4x = - sin 2x

2 sin 2x cos 2x = - sin 2x

sin(2x) (1+2cos(2x)) = 0.

So sin(2x) = 0 => x = 0, 90, 180, etc.

Or cos(2x) = -1/2. => x = 60, 120, etc

is this the only method of doing it?

i mean..i know this method but the question wanted me to use the sum and product formula

which is

2Sin((X+Y)/2)Cos((X-Y)/2)

from SinX and SinY

how do you use this formula and do it?

nopes its p2

i never said it was p3

i never said it was p3

erm...so can anyone answer this question?

i need to really solve it...someone help me pls

i need to really solve it...someone help me pls

MalaysianDude

yo all..

just wondering if you can help me with this

Sin4X + Sin2X = 0

i used the sum and product formula to get

2Sin3XCosX = 0

then im stuck

can someone help me out?

just wondering if you can help me with this

Sin4X + Sin2X = 0

i used the sum and product formula to get

2Sin3XCosX = 0

then im stuck

can someone help me out?

2sin3xcosx = 0

sin3xcosx = 0

Then sin3x = 0 or cosx = 0, and solve.

XTinaA

2sin3xcosx = 0

sin3xcosx = 0

Then sin3x = 0 or cosx = 0, and solve.

sin3xcosx = 0

Then sin3x = 0 or cosx = 0, and solve.

erm..

you sure thats the way?

argh..

iw as so careless :P

heehhe

thx anyways

- The Directrix of a Parabola
- Quatum Mechanics Primer Isaac Physics
- btec science unit 7 part a release 2023 january
- ART GCSE celebration
- Ocr law alevel h418
- Last minute research project!!! Help
- Macbeth gcse/igcse help + annotations
- Help urgent computer science
- macbeth gcse igcse annotations and help
- inspector calls revision help gcse
- CB1/CB2/CB3/CB9 exam
- cb1,cb2,cb3, cb9 exam gcse edexcel bio
- Help on choosing an epq
- CB1/CB2/CB3/CB9 exam Edexcel GCSE
- Cas shield login request
- sociology gcse
- IGCSE English language B ❤️😭 23 May 2023
- Help me graduate pls 😭| Survey for my final year project
- Gcse english revision
- Gcse results

Latest

Trending

Last reply 22 minutes ago

AQA GCSE English Literature Paper 1 (8702/1) - 13th May 2024 [Exam Chat]Last reply 1 hour ago

Grow Your Grades:Adam's Starting YR12 and Sixth Form Grow Your Grades BlogGrow your Grades

22

484

Last reply 2 hours ago

AQA GCSE English Language Paper 1 (8700/1) - 23rd May 2024 [Exam Chat]Last reply 1 day ago

AQA GCSE English Literature Paper 2 (8702/2) - 20th May 2024 [Exam Chat]English exams and study help

300

1243

Last reply 6 days ago

Edexcel GCSE Mathematics Paper 1 Higher (1MA1 1H) - 16th May 2024 [Exam Chat]Maths Exams

420

1461

Last reply 1 week ago

Edexcel GCSE Physics Paper 1 Higher (1PH0/1H) - 22nd May 2024 [Exam Chat]Physics Exams

82

280

Last reply 1 week ago

Edexcel GCSE Biology Paper 1 (Higher)(1B10/1H) - 10th May 2024 [Exam Chat]Biology Exams

140

423

Last reply 2 weeks ago

AQA GCSE Biology Paper 1 (Higher Combined) 8464/1H - 10th May 2024 [Exam Chat]Biology Exams

152

317

Last reply 2 weeks ago

AQA A-Level Chemistry Paper 1 (7405/1) - 10th June 2024 [Exam Chat]Chemistry Exams

388

2079

Last reply 2 weeks ago

Edexcel A-Level Geography Paper 1 | 16th May 2024 [Exam Chat]Last reply 2 weeks ago

Unofficial Mark scheme GCSE AQA Trilogy Combined Biology Paper 1 Higher 10th May 2024Biology Exams

25

37

Last reply 3 weeks ago

OCR A-Level Biology A Paper 1 (H420/01) - 5th June 2024 [Exam Chat]Biology Exams

331

1490

Last reply 4 weeks ago

Edexcel A Level Mathematics Paper 1 (9MA0 01) - 4th June 2024 [Exam Chat]Maths Exams

552

1453