English

Find the approximate value of cos (60° 30').

Advertisements
Advertisements

Question

Find the approximate value of cos (60° 30').

(Given: 1° = 0.0175c, sin 60° = 0.8660)

Advertisements

Solution

Let `f(X)=cosx`

`f'(x)=-sinx`

`x=60^@30'=60^@+(1/2)^@=a+h`

Here, `a=60^@=pi/3`

and `h=(1/2)^@=(0.0175)/2=0.00875`

`f(a)=f(pi/3)=cos(pi/3)=1/2=0.5`

`f'(a)=f'(pi/3)=-sin(pi/3)=-0.8660`

`f(a+h)~~f(a)+hf'(a)`

`cos(60^@30')~~0.5+(0.00875)(-0.8660)`

`~~0.5-0.0075775`

`~~0.4924`

shaalaa.com
  Is there an error in this question or solution?
2016-2017 (July)

APPEARS IN

Video TutorialsVIEW ALL [2]

RELATED QUESTIONS

Using differentials, find the approximate value of the following up to 3 places of decimal

`sqrt(49.5)`


Using differentials, find the approximate value of the following up to 3 places of decimal

`(0.999)^(1/10)`


Using differentials, find the approximate value of the following up to 3 places of decimal

`(26)^(1/3)`


Using differentials, find the approximate value of the following up to 3 places of decimal

`(401)^(1/2)`


Using differentials, find the approximate value of the following up to 3 places of decimal

`(0.0037)^(1/2)`


Using differentials, find the approximate value of the following up to 3 places of decimal

`(81.5)^(1/4)`


Find the approximate change in the volume ‘V’ of a cube of side x metres caused by decreasing the side by 1%.


The pressure p and the volume v of a gas are connected by the relation pv1.4 = const. Find the percentage error in p corresponding to a decrease of 1/2% in v .


Using differentials, find the approximate values of the cos 61°, it being given that sin60° = 0.86603 and 1° = 0.01745 radian ?


Using differential, find the approximate value of the \[\left( 80 \right)^\frac{1}{4}\] ?


Using differential, find the approximate value of the \[\sqrt{26}\] ?


Using differential, find the approximate value of the  \[\sqrt{0 . 48}\] ?


Using differential, find the approximate value of the  \[\sqrt{0 . 082}\] ?


Using differential, find the approximate value of the \[{25}^\frac{1}{3}\] ?


Find the approximate value of f (2.01), where f (x) = 4x2 + 5x + 2 ?


Find the approximate value of f (5.001), where f (x) = x3 − 7x2 + 15 ? 


Find the approximate change in the surface area of a cube of side x metres caused by decreasing the side by 1% ?


Find the approximate change in the value V of a cube of side x metres caused by increasing the side by 1% ?


If y = loge x, then find ∆y when x = 3 and ∆x = 0.03 ?


If the percentage error in the radius of a sphere is α, find the percentage error in its volume ?


A sphere of radius 100 mm shrinks to radius 98 mm, then the approximate decrease in its volume is


For the function y = x2, if x = 10 and ∆x = 0.1. Find ∆y.


Find the approximate values of : `sqrt(8.95)`


Find the approximate values of : `root(5)(31.98)`


Find the approximate values of : cos(60° 30°), given that 1° = 0.0175°, `sqrt(3) = 1.732`


Find the approximate values of : cot–1 (0.999)


Find the approximate values of : tan–1 (1.001)


Find the approximate values of : e0.995, given that e = 2.7183.


Find the approximate values of : loge(9.01), given that log 3 = 1.0986.


Find the approximate values of : f(x) = x3 + 5x2 – 7x + 10 at x = 1.12.


The approximate value of tan (44°30'), given that 1° = 0.0175c, is ______.


Using differentiation, approximate value of f(x) = x2 - 2x + 1 at x = 2.99 is ______.


Find the approximate value of (1.999)5.


Find the approximate value of f(3.02), where f(x) = 3x2 + 5x + 3


If `(x) = 3x^2 + 15x + 5`, then the approximate value of `f(3.02)` is


The approximate value of f(x) = x3 + 5x2 – 7x + 9 at x = 1.1 is ______.


Find the approximate value of sin (30° 30′). Give that 1° = 0.0175c and cos 30° = 0.866


Share
Notifications

Englishहिंदीमराठी


      Forgot password?
Use app×