$(\mathrm{sin}x{)}^{7}=a\mathrm{sin}7x+b\mathrm{sin}5x+c\mathrm{sin}3x+d\mathrm{sin}x$

for all angles $x$. Find $d$

mistergoneo7
2022-07-15
Answered

There exist constants $b$, and $d$ such that

$(\mathrm{sin}x{)}^{7}=a\mathrm{sin}7x+b\mathrm{sin}5x+c\mathrm{sin}3x+d\mathrm{sin}x$

for all angles $x$. Find $d$

$(\mathrm{sin}x{)}^{7}=a\mathrm{sin}7x+b\mathrm{sin}5x+c\mathrm{sin}3x+d\mathrm{sin}x$

for all angles $x$. Find $d$

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