1. -16
2. 0
3. -4 and 4
4. (4x-1)(4x+1)
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
(2*5^2)+4/3^2-5
(2*25)+4/3^2-5
50+4/3^2-5
50+1.7-5
46.7
Note down below rules for sign notations