Saved Bookmarks
| 1. |
Find e local maximum and local minima, of the function `f(x)= sin x-cos x`,`0 |
|
Answer» Here, `f(x) = sinx-cosx` `f(x) = sqrt2(1/sqrt2sinx-1/sqrt2cosx)` `= sqrt2(cos(pi/4) sinx-sin(pi/4) cosx)` `=sqrt2(sin(x-pi/4))` So, `f(x)` will be maximum when `sin(x-pi/4) = 1` `=> sin(x-pi/4) = sinpi/2=> x-pi/4 = pi/2=>x = (3pi/4)` `f(x)` will be minimum when `sin(x-pi/4) = -1` `=> sin(x-pi/4) = sin-pi/2=> x-pi/4 = -pi/2=>x = (-pi/4)` `:. f(x)_(max) = sqrt2` `f(x)_(min) = -sqrt2` |
|