Question

sinπ/11+sinπ/7-sin6π/7-sin10π/11

E1=sin70grade+sin40grade/sin250grade+sin220grade

Answer 1

Răspuns:

a) = 0

b) = $\frac{1}{sin^3^6^0}$

Explicație pas cu pas:

$a) \frac{sin\pi }{11} +\frac{sin\pi }{7} -\frac{sin6\pi }{7} -\frac{sin10\pi }{y}= \frac{sin\pi-sin10\pi }{11} +\frac{sin\pi-sin6\pi }{7}$, amplificam prima fractie cu 7, iar pe a doua cu 11; $\frac{(sin\pi-sin10\pi)*7 }{77}+\frac{(sin\pi-sin6\pi )*11 }{77} =\frac{0}{77} +\frac{0}{77} =\frac{0}{77} =0$

$b) \frac{sin^7^0+sin^4^0}{sin^2^5^0+sin^2^2^0} =\frac{sin^1^1^0}{sin^4^7^0} =sin^1^1^0^-^4^7^0=sin^-^3^6^0=\frac{1}{sin^3^6^0}$