Find the value of A such that the vectors  and  are perpendi

Previous Year Papers

Download Solved Question Papers Free for Offline Practice and view Solutions Online.

Test Series

Take Zigya Full and Sectional Test Series. Time it out for real assessment and get your results instantly.

Test Yourself

Practice and master your preparation for a specific topic or chapter. Check you scores at the end of the test.
Advertisement

 Multiple Choice QuestionsShort Answer Type

141.

If straight a with rightwards arrow on top space equals space 3 straight i with hat on top space plus space 2 straight j with hat on top space plus space 9 straight k with hat on top space and space straight b with rightwards arrow on top space equals space straight i with hat on top space plus space straight lambda straight j with hat on top space plus space 3 straight k with hat on top comma find the value of straight lambda so that straight a with rightwards arrow on top plus straight b with rightwards arrow on top is perpendicular to straight a with rightwards arrow on top minus straight b with rightwards arrow on top.

73 Views

142.

Let straight a with rightwards arrow on top space equals space 5 straight i with hat on top space minus space straight j with hat on top space plus space 7 straight k with hat on top and straight b with rightwards arrow on top space equals straight i with hat on top minus straight j with hat on top plus straight lambda straight k with hat on top. Find straight lambda such that straight a with rightwards arrow on top plus straight b with rightwards arrow on top and straight a with rightwards arrow on top minus straight b with rightwards arrow on top are orthogonal .

74 Views

143.

Find straight lambda if the vectors 5 straight i with hat on top plus 2 straight j with hat on top minus straight k with hat on top and straight lambda straight i with hat on top space minus space straight j with hat on top space plus space 5 space straight k with hat on top are orthogonal.

75 Views

144.

If straight a with rightwards arrow on top space equals space 2 space straight i with hat on top space plus space 2 space straight j with hat on top space plus space 3 space straight k with hat on top comma space space space straight b with rightwards arrow on top space equals negative straight i with hat on top space plus space 2 space straight j with hat on top space plus space straight k with hat on top space space and space straight c with rightwards arrow on top space equals 3 straight i with hat on top space plus space straight j with hat on top such that straight a with rightwards arrow on top space plus space straight lambda straight b with rightwards arrow on top is perpendicular to straight c with rightwards arrow on top, then find the value of straight lambda.

73 Views

Advertisement

 Multiple Choice QuestionsLong Answer Type

Advertisement

145. Find the value of A such that the vectors 3 straight a with rightwards arrow on top plus space 4 straight b with rightwards arrow on top and 2 straight a with rightwards arrow on top space plus space straight b with rightwards arrow on top are perpendicular to each other when 


        straight a with rightwards arrow on top space equals space straight i with hat on top space plus space 2 space straight j with hat on top space minus space 3 space straight k with hat on top comma space space straight b with rightwards arrow on top space equals space straight i with hat on top space plus space straight lambda space straight j with hat on top space plus space space 5 space straight k with hat on top.
Here,  straight a with rightwards arrow on top space equals space straight i with hat on top space plus space 2 space straight j with hat on top space minus space 3 space straight k with hat on top comma space space space straight b with rightwards arrow on top space equals space straight i with hat on top space plus space straight lambda space straight j with hat on top space plus space 5 space straight k with hat on top
therefore space space space 3 space straight a with rightwards arrow on top space plus space 4 space straight b with rightwards arrow on top space equals space 3 space left parenthesis straight i with hat on top space plus space 2 space straight j with hat on top space minus space 3 space straight k with hat on top right parenthesis plus space 4 space left parenthesis straight i with hat on top space plus space straight lambda space straight j with hat on top space plus space 5 space straight k with hat on top right parenthesis
                              equals 7 straight i with hat on top plus left parenthesis 6 plus 4 straight lambda right parenthesis straight j with hat on top space plus 11 space straight k with hat on top
and 2 straight a with rightwards arrow on top plus straight b with rightwards arrow on top space equals space 2 left parenthesis straight i with hat on top plus 2 straight j with hat on top space minus 3 straight k with hat on top right parenthesis space plus space left parenthesis straight i with hat on top plus straight lambda straight j with hat on top space plus space 5 straight k with hat on top right parenthesis
                     equals space 3 straight i with hat on top plus left parenthesis 4 plus straight lambda right parenthesis straight j with hat on top space minus space straight k with hat on top
Since 3 straight a with rightwards arrow on top plus space 4 straight b with rightwards arrow on top space and space 2 straight a with rightwards arrow on top plus straight b with rightwards arrow on top are perpendicular to each other
 therefore space space space left parenthesis 3 straight a with rightwards arrow on top space plus space 4 straight b with rightwards arrow on top right parenthesis. space left parenthesis 2 straight a with rightwards arrow on top plus straight b with rightwards arrow on top right parenthesis space equals space 0
therefore space space space left curly bracket 7 straight i with hat on top plus left parenthesis 6 plus 4 straight lambda right parenthesis space straight j with hat on top space plus space 11 space straight k with hat on top right curly bracket. space open curly brackets 3 straight i with hat on top space plus left parenthesis 4 plus straight lambda right parenthesis space straight j with hat on top space minus space straight k with hat on top close curly brackets space equals space 0
therefore space left parenthesis 7 right parenthesis thin space left parenthesis 3 right parenthesis space plus space left parenthesis 6 plus 4 space straight lambda right parenthesis space left parenthesis 4 plus straight lambda right parenthesis plus left parenthesis 11 right parenthesis thin space left parenthesis negative 1 right parenthesis space equals space 0
therefore space space space 21 plus 24 plus 22 straight lambda space plus space 4 straight lambda squared minus 11 space equals space 0
therefore space space space 4 straight lambda squared space plus 22 straight lambda space plus 34 space equals space 0
rightwards double arrow space space space 2 straight lambda squared plus 11 straight lambda plus 22 space equals space 0
therefore space space space straight lambda space equals space fraction numerator negative 11 plus-or-minus square root of 121 minus 176 end root over denominator 4 end fraction equals space fraction numerator negative 11 plus-or-minus square root of negative 55 end root over denominator 2 end fraction
there exist no real value of A.

75 Views

Advertisement

 Multiple Choice QuestionsShort Answer Type

146.

If open vertical bar straight a with rightwards arrow on top close vertical bar space equals space square root of 3 comma space space open vertical bar straight b with rightwards arrow on top close vertical bar space equals space 2 space and space straight a with rightwards arrow on top. space straight b with rightwards arrow on top space equals space 3 comma find the angle between straight a with rightwards arrow on top space and space straight b with rightwards arrow on top.

81 Views

147. Find the angle between two vectors straight a with rightwards arrow on top space and space straight b with rightwards arrow on top with magnitude 1 and 2 respectively and such that straight a with rightwards arrow on top. space straight b with rightwards arrow on top space equals space 1
79 Views

148.

If straight a with rightwards arrow on top space and space straight b with rightwards arrow on top are two vectors such that open vertical bar straight a with rightwards arrow on top close vertical bar space equals space 4 comma space space open vertical bar straight b with rightwards arrow on top close vertical bar space equals space 3 space space and space straight a with rightwards arrow on top comma space straight b with rightwards arrow on top space equals space 6 find the angle between straight a with rightwards arrow on top space and space straight b with rightwards arrow on top.

75 Views

Advertisement
149.

Find the angle between two vectors straight a with rightwards arrow on top space and space straight b with rightwards arrow on top with magnitudes 2  and 1 respectively, and such that straight a with rightwards arrow on top space. space straight b with rightwards arrow on top space equals space square root of 3.

75 Views

150.

Find the angle between two vectors straight a with rightwards arrow on top space and space straight b with rightwards arrow on top with magnitudes square root of 3 space and space 2 comma space respectively comma space and space that space space straight a with rightwards arrow on top. space straight b with rightwards arrow on top space equals space square root of 6.

90 Views

Advertisement