Answer:
(1 - 2sinα)(1 + 2sinα)
Step-by-step explanation:
1 - 4sin²α ← is a difference of squares and factors in general as
a² - b² = (a - b)(a + b)
1 - 4sin²α
= 1² - (2sinα )²
= (1 - 2sinα)(1 + 2sinα)
