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In f (x)= [{:(cos x ^(2),, x lt 0), ( si...

In `f (x)= [{:(cos x ^(2),, x lt 0), ( sin x ^(3) -|x ^(3)-1|,, x ge 0):}` then find the number of points where `g (x) =f (|x|)` is non-differentiable.

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To solve the problem, we need to analyze the function \( g(x) = f(|x|) \) based on the given piecewise function \( f(x) \). ### Step 1: Define the function \( f(x) \) The function \( f(x) \) is defined as: \[ f(x) = \begin{cases} \cos(x^2) & \text{if } x < 0 \\ \sin(x^3) - |x^3 - 1| & \text{if } x \geq 0 \end{cases} \] ### Step 2: Rewrite \( g(x) \) Since \( g(x) = f(|x|) \), we need to consider the absolute value of \( x \): - For \( x < 0 \), \( |x| = -x \) so \( g(x) = f(-x) = \cos((-x)^2) = \cos(x^2) \). - For \( x \geq 0 \), \( |x| = x \) so \( g(x) = f(x) = \sin(x^3) - |x^3 - 1| \). Thus, we can rewrite \( g(x) \) as: \[ g(x) = \begin{cases} \cos(x^2) & \text{if } x < 0 \\ \sin(x^3) - |x^3 - 1| & \text{if } x \geq 0 \end{cases} \] ### Step 3: Analyze \( g(x) \) for differentiability We need to check the differentiability of \( g(x) \) at the points where the definition of \( g(x) \) changes, which are \( x = 0 \) and \( x = 1 \). #### Check at \( x = 0 \): For \( x < 0 \): \[ g(x) = \cos(x^2) \] For \( x \geq 0 \): \[ g(x) = \sin(x^3) - |x^3 - 1| \] To check differentiability at \( x = 0 \), we need to find the left-hand and right-hand derivatives. **Left-hand derivative at \( x = 0 \)**: \[ g'(0^-) = \lim_{h \to 0^-} \frac{g(h) - g(0)}{h} = \lim_{h \to 0^-} \frac{\cos(h^2) - g(0)}{h} \] Since \( g(0) = \sin(0) - |0 - 1| = 0 - 1 = -1 \), \[ g'(0^-) = \lim_{h \to 0^-} \frac{\cos(h^2) + 1}{h} \] As \( h \to 0 \), \( \cos(h^2) \to 1 \), so: \[ g'(0^-) = \lim_{h \to 0^-} \frac{2}{h} \to -\infty \text{ (not defined)} \] **Right-hand derivative at \( x = 0 \)**: \[ g'(0^+) = \lim_{h \to 0^+} \frac{g(h) - g(0)}{h} = \lim_{h \to 0^+} \frac{\sin(h^3) - |h^3 - 1| + 1}{h} \] For small \( h \), \( |h^3 - 1| = 1 - h^3 \), thus: \[ g'(0^+) = \lim_{h \to 0^+} \frac{\sin(h^3) + h^3}{h} \] As \( h \to 0 \), \( \sin(h^3) \to 0 \): \[ g'(0^+) = \lim_{h \to 0^+} \frac{h^3}{h} = 0 \] Since \( g'(0^-) \) and \( g'(0^+) \) are not equal, \( g(x) \) is non-differentiable at \( x = 0 \). #### Check at \( x = 1 \): For \( x < 1 \): \[ g(x) = \sin(x^3) - |x^3 - 1| = \sin(x^3) - (1 - x^3) = \sin(x^3) + x^3 - 1 \] For \( x \geq 1 \): \[ g(x) = \sin(x^3) - (x^3 - 1) = \sin(x^3) - x^3 + 1 \] **Left-hand derivative at \( x = 1 \)**: \[ g'(1^-) = \lim_{h \to 1^-} \frac{g(h) - g(1)}{h - 1} \] Calculating \( g(1) \): \[ g(1) = \sin(1^3) + 1 - 1 = \sin(1) \] Thus: \[ g'(1^-) = \lim_{h \to 1^-} \frac{\sin(h^3) + h^3 - 1 - \sin(1)}{h - 1} \] **Right-hand derivative at \( x = 1 \)**: \[ g'(1^+) = \lim_{h \to 1^+} \frac{g(h) - g(1)}{h - 1} \] Calculating: \[ g'(1^+) = \lim_{h \to 1^+} \frac{\sin(h^3) - h^3 + 1 - \sin(1)}{h - 1} \] Since both derivatives yield different results, \( g(x) \) is also non-differentiable at \( x = 1 \). ### Conclusion The points where \( g(x) \) is non-differentiable are \( x = 0 \) and \( x = 1 \). Therefore, the number of points where \( g(x) \) is non-differentiable is **2**.
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VK JAISWAL ENGLISH-CONTINUITY, DIFFERENTIABILITY AND DIFFERENTIATION-EXERCISE (SUBJECTIVE TYPE PROBLEMS)
  1. If y ^(2) =4ax, then (d^(2) y)/(dx ^(2))=(ka ^(2))/( y ^(2)), where k ...

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  2. The number of values of x , x ∈ [-2,3] where f (x) =[x ^(2)] sin (pix)...

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  3. If f (x) is continous and differentiable in [-3,9] and f'(x) in [-2,8]...

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  4. In f (x)= [{:(cos x ^(2),, x lt 0), ( sin x ^(3) -|x ^(3)-1|,, x ge 0)...

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  5. Consider f(x) =x^(2)+ax+3 and g(x) =x+band F(x) = lim( n to oo) (f...

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  6. Let f (x)= {{:(2-x"," , -3 le x le 0),( x-2"," , 0 lt x lt 4):} Then f...

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  7. If f (x) +2 f (1-x) =x ^(2) +2 AA x in R and f (x) is a differentiable...

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  8. Let f (x)= signum (x) and g (x) =x (x ^(2) -10x+21), then the number o...

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  9. If (d^(2))/(d x ^(2))((sin ^(4)x+ sin ^(2)x+1)/(sin ^(2)x + si n x+1))...

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  10. f (x) =a cos (pix)+b, f'((1)/(2))=pi and int (1//2)^(3//2) f (x) dx =2...

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  11. Let alpha (x) = f(x) -f (2x) and beta (x) =f (x) -f (4x) and alpha '(1...

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  12. Let f (x) =-4.e ^((1-x)/(2))+ (x ^(3))/(3 ) + (x ^(2))/(2)+ x+1 and g ...

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  13. If y=3^(2 sin ^(-1)) then |((x ^(2) -1) y^('') +xy')/(y)| is equal to

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  14. Let f (x)=x+ (x ^(2))/(2 )+ (x ^(3))/(3 )+ (x ^(4))/(4 ) +(x ^(5))/(5)...

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  15. In f (x)= [{:(cos x ^(2),, x lt 0), ( sin x ^(3) -|x ^(3)-1|,, x ge 0)...

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  16. For the curve sinx+siny=1 lying in first quadrant. If underset(xrarr0...

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  17. Let f (x) = x tan ^(-1) (x^(2)) + x^(4) Let f ^(k) (x) denotes k ^(th)...

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  18. If x = cos theta and y = sin^(3) theta, then |(yd ^(2)y)/(dx ^(2))+((d...

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  19. The value of x, x in (2,oo) where f (x) = sqrt(x sqrt(8x-16))+ sqrt(x-...

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  20. The number of non differentiability of runction f (x) = min (|x| , {x}...

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