Home
Class 12
MATHS
Prove that the determinant [xsinthetacos...

Prove that the determinant `[xsinthetacostheta-sintheta-x1costheta1x]`is independent of 0.

Text Solution

Verified by Experts

`[{:(x,"sin"theta,"cos"theta),("-sin"theta,-x,1),("cos"theta,1,x):}]`
`[{:(-x,1),(1,x):}]"-sin"theta[{:("-sin"theta,1),("cos"theta,x):}]"+cos"theta|{:("-sin"theta,-x),("cos"theta,1):}|`
`=x(-x^(2)-1)-"sin"theta(-x"sin"theta-"cos"theta)+"cos"theta(-"sin"theta"+x"cos"theta)`
`=-x^(3)-x+x"sin"^(2)theta+"sin"theta"cos"theta-"sin"theta"cos"theta+x"cos"^(2)theta`
`=-x^(3)-x+x(sin^(2)theta+cos^(2)theta)`
`=-x^(3)-x+x=-x^(3)`
Doubtnut Promotions Banner Mobile Dark
|

Topper's Solved these Questions

  • DETERMINANTS

    NAGEEN PRAKASHAN|Exercise Exercise 4.6|16 Videos
  • Continuity and Differentiability

    NAGEEN PRAKASHAN|Exercise Miscellaneous Exercise|23 Videos
  • DIFFERENTIAL EQUATIONS

    NAGEEN PRAKASHAN|Exercise Miscellaneous Exercise|18 Videos

Similar Questions

Explore conceptually related problems

Prove that the determinant |[x, sintheta,costheta],[-sintheta,-x,1],[costheta,1,x]| is independent of theta

Prove that the determinate abs([x,sintheta,costheta],[-sintheta,-x,1],[costheta,1,x]) is independent of theta

Knowledge Check

  • Determinant A=|(x,sintheta,costheta),(-sintheta,-x,1),(costheta,1,x)|

    A
    Independent of `theta`
    B
    dependent of `theta`
    C
    dependent of `theta` and x
    D
    None of the above
  • If sintheta+costheta=x then sintheta-costheta=?

    A
    `pmsqrt(2-x^(2))`
    B
    `pmsqrt(2+x^(2))`
    C
    `pmsqrt(4-x^(2))`
    D
    `pmsqrt(4+x^(2))`
  • (sintheta-costheta+1)/(sintheta+costheta-1) is equal to

    A
    `(1)/(tan theta - sec theta)`
    B
    `(1)/(sec theta - tan theta)`
    C
    `(1)/(cos theta - tan theta)`
    D
    `(1)/(tan theta - cos theta)`
  • Similar Questions

    Explore conceptually related problems

    Prove that the determinant |[x,sin theta,cos theta],[-sin theta,-x,1],[cos theta,1,x]| is independent of

    Prove that the determinant |{:(x,sintheta,costheta),(-sintheta,-x,1),(costheta,1,x):}| is independent of theta .

    Prove that |[x, sintheta, costheta],[-sintheta, -x, 1],[costheta, 1, x]| is independent of theta

    If |xsinthetacostheta-sintheta-x1costheta1x|=8 , write the value of xdot

    Prove that the determinant Delta =|{:(x,,sintheta,,cos theta),(-sin theta,,-x,,1),(cos theta,,1,,x):}| is independent of theta .