$( \arcsin{x})'= \frac{1}{ \sqrt{1-x^2} } 
\\
\\ (\arcsin{(2x+1)})'= \frac{1}{ \sqrt{1-(2x+1)^2} } (2x+1)'= \frac{2}{ \sqrt{1-(4x^2+4x+1)} } =
\\
\\= \frac{2}{ \sqrt{-4x^2-4x} } =\frac{2}{ \sqrt{4x(-x-1} )} =\frac{2}{ 2\sqrt{x(-x-1} )} =\frac{1}{ \sqrt{x(-x-1} )}$

3 0

3 years ago

Maya added 5 grams of salt into 20 grams of 50% salt solution. She made ___ grams of ___% salt solution.

AlladinOne [14]

Consider the suggested option:
1) if in 20 gr. of 50% solution given, then pure salt in this mix is 0.5*20=10 gr., and pure water is 0.5*20=10 gr.
2) after Maya added 5 gr. pure salt is 10+5=15 gr. Total mass of mix is 15(pure salt)+10(pure water)=25 gr.
3) new solution is 15/25=0.6 or 60%.
Answer: 25 gr. of 60% salt solution.

7 0

3 years ago