No products in the cart.

4. Prove that sin^2 (8x) - …

CBSE, JEE, NEET, CUET

CBSE, JEE, NEET, CUET

Question Bank, Mock Tests, Exam Papers

NCERT Solutions, Sample Papers, Notes, Videos

4. Prove that sin^2 (8x) - sin^2 (3x) =sin 11x.sin 5x 04 1
  • 3 answers

Shivam Jha 3 months, 1 week ago

As we know, Sin²x - Sin²y = Sin(x+y) Sin(x-y) Thus, Sin²8x - Sin²3x = (Sin8x + Sin3x) X (Sin8x - Sin3x) Since, Sinx + Siny = 2Sin[(x+y)/2] Cos[(x-y)/2] Sinx + Siny = 2Cos[(x+y)/2] Sin[(x-y)/2] (2Sin11x/2 X Cos5x/2) X (2Cos11x/2 X Sin5x/2) (2 Sin11x/2 X Cos11x/2) X (2 Sin5x/2 X Cos5x/2) Sin11x X Sin5x H.P! {2SinxCosx = Sin2x}
There's a mistake done by me.. Sin(8x+3x).Sin(8x-3x) = sin11x.sin5x
As we knw that, sin²x - sin²y = sin(x+y)sin(x-y) Therefore, Sin² 8x - Sin² 3x = Sin (8x+3x). × Sin(8x-3x) Sin11x.sin5x Hence LHS=RHS (proved)
http://mycbseguide.com/examin8/

Related Questions

Log1/a^81
  • 0 answers
A-(B-C)=(A-B)-C of sets
  • 0 answers
Option of photo
  • 0 answers

myCBSEguide App

myCBSEguide

Trusted by 1 Crore+ Students

Test Generator

Test Generator

Create papers online. It's FREE.

CUET Mock Tests

CUET Mock Tests

75,000+ questions to practice only on myCBSEguide app

Download myCBSEguide App