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

`(0.009)^(1/3)`


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

`(255)^(1/4)`


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

`(26.57)^(1/3)`


If the radius of a sphere is measured as 7 m with an error of 0.02m, then find the approximate error in calculating its volume.


If f (x) = 3x2 + 15x + 5, then the approximate value of (3.02) is

A. 47.66

B. 57.66

C. 67.66

D. 77.66


The normal at the point (1, 1) on the curve 2y + x2 = 3 is

(A) x + y = 0

(B) x − = 0

(C) x + y + 1 = 0

(D) − y = 1


Find the approximate value of log10 (1016), given that log10e = 0⋅4343.


Find the percentage error in calculating the surface area of a cubical box if an error of 1% is made in measuring the lengths of edges of the cube ?


The height of a cone increases by k%, its semi-vertical angle remaining the same. What is the approximate percentage increase (i) in total surface area, and (ii) in the volume, assuming that k is small ?


1 Using differential, find the approximate value of the following:

\[\sqrt{25 . 02}\]


Using differential, find the approximate value of the following:  \[\left( 0 . 009 \right)^\frac{1}{3}\]


Using differential, find the approximate value of the \[\left( 15 \right)^\frac{1}{4}\] ?


Using differential, find the approximate value of the \[\frac{1}{(2 . 002 )^2}\] ?


Using differential, find the approximate value of the \[\left( 66 \right)^\frac{1}{3}\] ?


Using differential, find the approximate value of the  \[\sqrt{37}\] ?


Using differential, find the approximate value of the \[\left( \frac{17}{81} \right)^\frac{1}{4}\] ?


Using differential, find the approximate value of the \[\sqrt{49 . 5}\] ?


Using differential, find the approximate value of the \[\left( 3 . 968 \right)^\frac{3}{2}\] ?


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 ? 


If the radius of a sphere is measured as 9 cm with an error of 0.03 m, find the approximate error in calculating its surface area ?


Find the approximate change in the surface area of a cube of side x metres caused by decreasing 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 piece of ice is in the form of a cube melts so that the percentage error in the edge of cube is a, then find the percentage error in its volume ?


Find the approximate value of f(3.02), up to 2 places of decimal, where f(x) = 3x2 + 5x + 3.


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


Find the approximate values of: `root(3)(28)`


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


Find the approximate values of sin (29° 30'), given that 1° = 0.0175°, `sqrt(3) = 1.732`.


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


Find the approximate values of : loge(101), given that loge10 = 2.3026.


Find the approximate values of : f(x) = x3 – 3x + 5 at x = 1.99.


If the radius of a sphere is measured as 9 m with an error of 0.03 m. the find the approximate error in calculating its surface area


Share
Notifications

Englishहिंदीमराठी


      Forgot password?
Use app×