Question

Find x + y if x= 13 sin^2 A and y=13 cos^2A+1​

Answer 1

Answer:

x+y=2n,n∈I.

Step-by-step explanation:

Given x−y=

3

1

....(1)

and cos

2

(πx)−sin

2

(πy)=

2

1

...(2)

⇒cosπ(x+y)cosπ(x−y)=

2

1

⇒cosπ(x+y)=1 (by (1))

⇒x+y=2n,n∈I.

Only option C satisfies above equation

Answer 2

Answer:

we will use sin² A + cos ² A = 1

Step-by-step explanation:

x + y

13 sin ² A + 13 cos ² A + 1

13 ( sin² A + cos ² A) + 1

13 × 1 + 1

13 + 1

14