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SMO 2008 Senior Round 1 Question 7

SMO · SMO 2008 Senior Round 1

Question 7

Find $\sin^4\frac\pi8+\sin^4\frac{3\pi}8+\sin^4\frac{5\pi}8+\sin^4\frac{7\pi}8$.
  1. $1$
  2. $3/2$
  3. $7/4$
  4. $2$
  5. $5/2$