maths _24

27)
By remainder theorem ,
f(-k)=2
(-k)^2+3(-k)-2=2
k^2-3k-4=0
k=4 or k=-1
Ans : D
25)

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24)

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Q 27.
By remainder therom
f (-k) = 2
(-k)^2 + 3 (-k) -2 = 2
k^2 - 3k - 4 = 0
(k-4)(k+1)=0
k = 4 or k = -1

Q. 25
Let E be the foot of V on plane ABCD
Let F be the mid. pt. of AB
as height = 4 cm
So EV = 4 cm
EF = 3/2 cm ( as ABCE is a square)
= 1.5 cm

angle between plane VAB and ABCD
= angle VFE
tan angle VFE = VE/EF
= 8/3

Q. 24
As you marked the angle of the right-angled isos. triangle as 45 degree
And the angle between line NO and OA is 180 - 90 -55 = 35
Add a horizontal line at A and the line cut NO ar C
angle OAC = 180 - 90 -35 = 55
angle CAB = 55+ 45 = 100

whole circle bearing take North as 0 degree and count the angle clockwise-ly. Therefore the angle = 360 - 100 - 90 = 170