y=√(1-x²)*arccosx
y'=[√(1-x²)]'arcsosx+√(1-x²)*(arccos)'
=(1/2)*(1-x²)ˆ(-1/2)*(1-x²)’+√(1-x²)*[-1/√(1-x²)]
=(1/2)*(1-x²)ˆ(-1/2)*(-2x)-1
=-x* [1/√(1-x²)]-1
=-x/√(1-x²)-1
y=√(1-x²)*arccosx
y'=[√(1-x²)]'arcsosx+√(1-x²)*(arccos)'
=(1/2)*(1-x²)ˆ(-1/2)*(1-x²)’+√(1-x²)*[-1/√(1-x²)]
=(1/2)*(1-x²)ˆ(-1/2)*(-2x)-1
=-x* [1/√(1-x²)]-1
=-x/√(1-x²)-1