3 years ago

Please can someone prove this equation

Mathematics

1 answer:

zubka84 [21]3 years ago

6 0

Answer:

see explanation

Step-by-step explanation:

Using the trigonometric identity

sin²x + cos²x = 1

Consider the left side

2cos²A - 1 ← replace 1 by sin²A + cos²A

= 2cos²A - ( sin²A + cos²A)

= 2cos²A - sin²A - cos²A

= cos²A - sin²A = right side ⇒ verified

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