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For which Domain, the functions f(x) = 2...

For which Domain, the functions `f(x) = 2x^2-1` and `g(x)=1-3x` are equal to

A

`[2,-1//2]`

B

`[-2,1//2]`

C

`[1,2]`

D

`[-2,-1//2]`

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The correct Answer is:
To determine the domain for which the functions \( f(x) = 2x^2 - 1 \) and \( g(x) = 1 - 3x \) are equal, we will follow these steps: ### Step 1: Set the functions equal to each other We start by equating the two functions: \[ f(x) = g(x) \] This gives us: \[ 2x^2 - 1 = 1 - 3x \] ### Step 2: Rearrange the equation Next, we rearrange the equation to bring all terms to one side: \[ 2x^2 + 3x - 1 - 1 = 0 \] This simplifies to: \[ 2x^2 + 3x - 2 = 0 \] ### Step 3: Factor the quadratic equation Now, we will factor the quadratic equation \( 2x^2 + 3x - 2 = 0 \). We look for two numbers that multiply to \( 2 \times -2 = -4 \) and add up to \( 3 \). The numbers \( 4 \) and \( -1 \) work: \[ 2x^2 + 4x - x - 2 = 0 \] Grouping the terms: \[ (2x^2 + 4x) + (-x - 2) = 0 \] Factoring by grouping: \[ 2x(x + 2) - 1(x + 2) = 0 \] This gives us: \[ (2x - 1)(x + 2) = 0 \] ### Step 4: Solve for \( x \) Now, we set each factor equal to zero: 1. \( 2x - 1 = 0 \) leads to: \[ 2x = 1 \implies x = \frac{1}{2} \] 2. \( x + 2 = 0 \) leads to: \[ x = -2 \] ### Step 5: Identify the domain The solutions \( x = \frac{1}{2} \) and \( x = -2 \) are the points where the two functions are equal. Since both functions are polynomial functions, their domain is all real numbers. Thus, the domain where the functions are equal is: \[ x = -2 \quad \text{and} \quad x = \frac{1}{2} \] ### Final Answer The functions \( f(x) \) and \( g(x) \) are equal at the points \( x = -2 \) and \( x = \frac{1}{2} \). ---

To determine the domain for which the functions \( f(x) = 2x^2 - 1 \) and \( g(x) = 1 - 3x \) are equal, we will follow these steps: ### Step 1: Set the functions equal to each other We start by equating the two functions: \[ f(x) = g(x) \] This gives us: ...
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OBJECTIVE RD SHARMA ENGLISH-FUNCTIONS-Chapter Test
  1. For which Domain, the functions f(x) = 2x^2-1 and g(x)=1-3x are equal ...

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  2. The number of bijective functions from set A to itself when A contains...

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  3. If f(x)=|sin x| then domain of f for the existence of inverse of

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  4. The function f:[-1//2,\ 1//2]->[-pi//2,pi//2\ ] defined by f(x)=s in^(...

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  5. Let f: R->R be a function defined by f(x)=(e^(|x|)-e^(-x))/(e^x+e^(-x)...

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  6. If f: (e,oo) rarr R & f(x)=log[log (logx)], then f is - (a)f is one-...

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  7. Let f: R-{n}->R be a function defined by f(x)=(x-m)/(x-n) , where m!=n...

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  8. Find the inverse of the function: f(x)=(e^(x)-e^(-x))/(e^(x)+e^(-x))+2

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  9. Find the inverse of the function :y=(1 0^x-1 0^(-x))/(1 0^x+1 0^(-x))+...

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  10. Let f(x+(1)/(x))=x^(2)+(1)/(x^(2)),(x ne 0) then f(x) equals

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  11. Let f : R rarr R, g : R rarr R be two functions given by f(x) = 2x - 3...

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  12. If g(x)=1+sqrtx and f(g(x))=3+2sqrtx+x then f(x) is equal to

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  13. If f(x)=(1-x)/(1+x), x ne 0, -1 and alpha=f(f(x))+f(f((1)/(x))), then

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  14. Let f:R to R be a function defined by f(x)=(x^(2)-8)/(x^(2)+2). Then f...

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  15. If f:(-oo,2]to (-oo,4] where f(x), then f ^(-1) (x) is given by :

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  16. Find the inverse of the function, (assuming onto). " " ...

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  17. f: R->R is defined by f(x)=(e^(x^2)-e^(-x^2))/(e^(x^2)+e^(-x^2)) is :

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  18. If f(x)=log((1+x)/(1-x))a n dt h e nf((2x)/(1+x^2)) is equal to {f(x)...

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  19. If f(x)=(2^x+2^(-x))/2 , then f(x+y)f(x-y) is equals to 1/2{f(2x)+f(2y...

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  20. The function f:R to R given by f(x)=x^(2)+x is

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  21. Let f:R to R and g:R to R be given by f(x)=3x^(2)+2 and g(x)=3x-1 for ...

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