sin-¹(-1/2) the answer is -π/6 how do I get that answer?
We have \[\sin^{-1} (-1/2)\]? do you know the range of \(\sin^{-1} x\)?
Are you here @SandyHearts ?
All it says is find the exact value of each expression. No range or anything.
I know that but do you know about \(\sin^{-1} x\)?
no i do not
Do you want me to tell you about it? then the problem will be solved in seconds!!
yes, of course.
oh wait the anser is -π/6
I just don't know how to get it.
Ok, I'll explain you. You know sin x?
what about it?
What is the range of sin x? I mean what's its minimum value and what is its maximum value?
0-180? i have no idea
You know when \[x =0\longrightarrow \sin x =0\] \[x =\pi/2\longrightarrow \sin x =1\] \[x =-\pi/2\longrightarrow \sin x =-1\] Do you get this?
yes I get this. Like in the unit circle.
Yeah, so sin x max value is 1 and min value is -1
You know the inverse of sin x is \(\sin^{-1}x\) Just like division is inverse of multiplication We multiply x by 2 and divide it by 2, we'll get back x Do you get this?
You know sin x repeats its value after \(2\pi\)? So we have fixed the range and domain of \(\sin^{-1} x\) \[ \text{x can only be between -1 and 1}\] \[\text{and its range is from }\frac{-\pi}{2} \text {to}\frac{\pi}{2}\] Do you get this?
yes
Ok tell me at what value of x , sin x =1/2?
sin-¹(1/2)=x @ash2326
I mean When \(x=60\ \sin x=\frac{\sqrt 3}{2}\) so for what value of x, sin x=1/2, check your unit circle and tell
π/6 ?
Yeah:D you're right so tell me know \[\sin^{-1} (-\frac{1}{2})=?\]
-π/6
Yay:D did you understand it?
Yes, thank you so much!
Welcome:D
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