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If there are two values of a which makes...

If there are two values of a which makes determinant,
`Delta=|(1,-2,5),(2,a,-1),(0,4,2a)|=86` then the sum of these number is

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Given`Delta=|(1,-2,5),(2,a,-1),(0,4,2a)|=86`
⇒`1(2a^2+4)−2(−4a−20)+0=86 `[expanding along first column ]
⇒`2a^2+4+8a+40=86`
⇒`2a^2+8a+44−86=0`
⇒`a^2+4a−21=0`
...
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RD SHARMA-DETERMINANTS-Solved Examples And Exercises
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  2. If 1.omega, omega^2 are the roots of unity, then Delta=|(1,omega^n,ome...

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  3. If a >0 and discriminant of a x^2+2b x+c is negative, then |[a,b,ax+...

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  9. Let A=[[1,sintheta,1],[sintheta,1,sintheta],[-1,-sintheta,1]] where 0l...

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  12. If x , y , z are different from zero and [[1+x,1, 1],[ 1 ,1+y,1 ],[1 ,...

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  15. The maximum value of =[[1, 1, 1],[ 1, 1+sintheta,1],[ 1,1,1+costheta]...

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  17. Let f(x)=|cosx x 1 2sinx x2xsinx x x| , then (lim)(x->0)(f(x))/(x^2) i...

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  18. If there are two values of a which makes determinant, Delta=|(1,-2,5...

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  19. If Delta=|(a,p,x),(b,q,y),(c,r,z)|=16 then Delta(1)=|(p+x,a+x,a+p),(q+...

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