# Recent content by thatguythere

1. ### Calculating masses of unknown quantities of reactants.

Homework Statement Calculate the number of moles and mass of BaCl2 and NaCl in the original mixture. Homework Equations We prepared a solution of 0.35M Na2SO4. We then obtained an unknown mixture of BaCl2•2H2O and NaCl, weighed 1 g and added it to 200 mL of water and 10 mL HCl. Finally we...
2. ### Evaluating an Inverse Trigonometric Function

I apologize for being so confused, independent study is not being kind to me. Thank you very much, your help is immensely appreciated.
3. ### Evaluating an Inverse Trigonometric Function

sin^-1(sin(20°))=20°=∏/9
4. ### Evaluating an Inverse Trigonometric Function

Alright. So if cos(90°-x)=sinx, which in my case is 70°, I still do not understand why Tanya then encourages me to use sin^-1(sinθ)=θ. How is cos70° to be replaced by sinθ? By the trig identities, sin(90°-x)=cosx, it is sin20° which is equivalent to cos70°. Would my equation then be accurately...
5. ### Evaluating an Inverse Trigonometric Function

Ah a trig identity I see. So cos(90°-70°)=sinθ cos(20°)=sinθ 0.94=sinθ sin^-1(sinθ)=θ sin^-1(0.94)=θ 0.94=θ
6. ### Evaluating an Inverse Trigonometric Function

Could you possibly explain the cos(90°-θ)=sinθ?
7. ### Evaluating an Inverse Trigonometric Function

Homework Statement Evaluate sin^-1(cos70°) Homework Equations The Attempt at a Solution sin^-1(cos70°)=θ sinθ=cos70° sinθ=1/2 sinθ=∏/3

Bump.
9. ### Derivative of Trigonometric Functions

Oh I guess I could change the term in the denominator to 4/3.
10. ### Derivative of Trigonometric Functions

Let's try this
11. ### Derivative of Trigonometric Functions

Can anyone tell me if I am on the right track please?
12. ### Derivative of Trigonometric Functions

((2/√3)(√3/3)+((2/√3)(1/3))-(8/3^(3/2)))/(4/3)+((2√3)/3) =(2/9+2/(3√3)-8/(3^3/2))/((2(2√3+1))/3√3)
13. ### Derivative of Trigonometric Functions

Yes, I was simply confusing myself. As far as my current work, can it be simplified any more?
14. ### Derivative of Trigonometric Functions

Is this as far as it goes? Can it be simplified any more?
15. ### Derivative of Trigonometric Functions

=((1+tanx)(secxtanx)-(secx)(sec^2x))/(1+tanx)2 =(secxtanx+secxtan^2x-sec^3x)/(1+tanx)2 Is this looking any closer to a correct answer?