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sin^2(A/2+pi/8) - sin^2(A/2-pi/8)= 1/sqr...

`sin^2(A/2+pi/8) - sin^2(A/2-pi/8)= 1/sqrt(2)sinA`

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Verified by Experts

Given,
`=sin^2(pi/8 + x/2) – sin^2(pi/8 – x/2) `
we know,
`sin^2A – sin^2B = sin(A + B) sin(A - B) `
So, `sin^2(pi/8 + x/2) – sin^2(pi/8 – x/2)`
`= sin(pi/8 + x/2 + pi/8 – x/2) sin (pi/8 + x/2 – (pi/8 – x/2)) `
`= sin (pi/8 + pi/8) sin (pi/8 + x/2 – pi/8 + x/2)`
`= sin ((2pi)/8) sin ((2x)/2)`
...
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RD SHARMA-TRIGONOMETRIC RATIOS OF MULTIPLE AND SUBMULTIPLE ANGLES-Solved Examples And Exercises
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