Application of DerivativeHard
Question
The d.r. of normal to the plane through (1, 0, 0) , (0, 1, 0) which makes an angle π/4 with plane x + y = 3 are
Options
A.1, √2, 1
B.1, 1, √2
C.1, 1, 2
D.√2, 1, 1
Solution
Equation of plane through (1, 0, 0) is
a(x - 1) + by + cz = 0 ........ (i)
(i) passes through (0, 1, 0)
- a + b = 0 ⇒ b = a; Also, cos 45o =
⇒ 2a =
⇒ 2a2 = c2 ⇒ c = √2a
So. d.r. of normal are a, a √2a i.e. 1,1,√2
a(x - 1) + by + cz = 0 ........ (i)
(i) passes through (0, 1, 0)
- a + b = 0 ⇒ b = a; Also, cos 45o =

⇒ 2a =
⇒ 2a2 = c2 ⇒ c = √2aSo. d.r. of normal are a, a √2a i.e. 1,1,√2
Create a free account to view solution
View Solution FreeMore Application of Derivative Questions
The maximum value of (cos α1).(cos α2) ...... (cos αn) under the restrictions 0 ≤ α1, α2,...Let p(x) = a0 + a1 x2 + a2x4 + ..... + anx2n be a polynomial ina real variable xwith 0 0 1 1 n The function P(x) has...If a + b + c = 0, then the equation 3ax2 + 2bx + c = 0 has, in the interval (0, 1) -...The radius of a circle is increasing at the rate of 0.7 cm/sec. The rate of increase of its circumference is -...The sum of the first n terms of the series 12 + 2.22 + 32 + 2.42 + 52 + 2.62 + ...... is when n is even. When n is odd, ...