Answer: sintheta = Π/2 + nΠ (D)
Step-by-step explanation:
If (sinx)(cosx) = 0...1
Note that sin2x = sinxcosx + cosxsinx = 2sinxcosx
If Sin2x = 2sinxcosx
(sinx)(cosx) = sin2x/2...2
Substituting equation 2 into 1
Sin2x/2 = 0
Sin2x = 0
2x = sin-¹0
2x = 90°
x = 45° = Π/2 (since 180° = Πrad)
General solution to sin function is
Sintheta = nΠ+(-1)^nΠ/2
Sintheta = nΠ+Π/2 (for n = all positive integers)
Sintheta = Π/2 + nΠ (D)