Step-by-step explanation:
all the details are in the attachment; the solution are is filled with purple color.
Step-by-step explanation:
To prove :
( 1 - sin x ) ( 1 + sin x ) = sec² x
LHS : -
( 1 - sin x ) ( 1 + sin x )
Formula / Identity : -
( a - b ) ( a + b ) = a² - b²
Here,
a = 1
b = sin x
( 1 - sin x ) ( 1 + sin x )
= 1 - sin² x
Identify : -
sin² θ + cos² θ = 1
cos² θ = 1 - sin² θ
Similarly,
1 - sin² x
= cos² x
= RHS
Hence verified.
Answer:
Step-by-step explanation:
we know that
---> by addition angle postulate
we have
----> given problem
----> given problem
substitute in the expression above
Divide by 2 both sides
B. 25/20 using gcf simplified is 5/4
