Question

2cos(45+a).cos(45-a)

Answer 1

Step-by-step explanation:

2 cos(45+a) cos(45-a)  

2 cos([45-45]+45+a) cos(45-a) [ have to change it to identity 2sinAcosA =sin2A ]  

2 cos(45+45 -45+a) cos(45-a)  

2 cos(90-(45-a)) cos(45-a)  

2 sin(45-a) cos(45-a)  

sin2(45-a)  

sin(90-2a)  

cos2a

Answer 2

hello frnd here's the answer to the given question hope ull get the answer to the given question and mark as brainliest one.........✌✌✌✌✌✌