Answer:
3 gallons
Step-by-step explanation:
Let
x ----> the amount of pure acid (100% solution) in gallons
Remember that



we know that

solve for x


therefore
3 gallons of pure acid should be mixed with 3 gallons of a 20% acid solution in order to get a 60% acid solution
That is hard. I'm guessing that they still are the same shapes but they all have different lengths in certain areas that make them seem like they are the same shapes but are being seen at different angles but I can't be sure. That's why they are in the same groups although having different angles. Does it have answer choices? I will help you if it does...
Answer:
∑ₙ₌₀°° 8 (-1)ⁿ x⁴ⁿ⁺¹ / (9ⁿ (2n)!)
Step-by-step explanation:
Start with the Maclaurin series for cos x.
cos x = ∑ₙ₌₀°° (-1)ⁿ x²ⁿ / (2n)!
Substitute ⅓ x².
cos (⅓ x²) = ∑ₙ₌₀°° (-1)ⁿ (⅓ x²)²ⁿ / (2n)!
cos (⅓ x²) = ∑ₙ₌₀°° (-1)ⁿ (⅓)²ⁿ x⁴ⁿ / (2n)!
cos (⅓ x²) = ∑ₙ₌₀°° (-1)ⁿ x⁴ⁿ / (9ⁿ (2n)!)
Multiply by 8x.
8x cos (⅓ x²) = ∑ₙ₌₀°° 8x (-1)ⁿ x⁴ⁿ / (9ⁿ (2n)!)
8x cos (⅓ x²) = ∑ₙ₌₀°° 8 (-1)ⁿ x⁴ⁿ⁺¹ / (9ⁿ (2n)!)
Answer:
90
Step-by-step explanation:
The step is 90×10=100