Can u help find the values of each of the following giving your answers correct to 3 decimal places, with workings pls.
(i) x^2e^(3x+1) when x = 0.1
(ii) 4e^-x cos 3x when x = 2 radians
(iii) 3 cosec x +7 cot x when x = 1 radian
(iv) 3 ln(cos x) when x = 0.1 radian
2007-01-14 00:02:22 · 5 answers · asked by SHIBZ 2 in Science & Mathematics ➔ Mathematics
(i) 0.1² x e^(1.3) = 0.1² x 2.718^(1.3) = 0.0367
(ii) 1 radian = 57.3 °, 6 radians = 349°
4e^(-2) cos(6) = (4/e^(2)) cos 349°
= (4 / 7.39) x 0.982 = 0.532
(iii) 3/sinx + 7cosx/sinx = 3/sin57.3 + 7cos57.3 / sin57.3
= 3/0.842 + 7 x 0.54/0.842
= 3.56 + 4.5 = 8.06
(iv) 3ln (cos x ) = 3ln(cos5.73°) = - 0.015
Rather difficult to type this out but hopefully you will be able to follow method!
2007-01-14 06:38:20 · answer #1 · answered by Como 7 · 0⤊ 0⤋
Just use your calculator. Make sure it's set in radians, and to do (iii), first do sin (1) then press the reciprocal (i.e. 1/x) button, multiply by 3, then do +7/tan(1). Sorry , I'm too sleepy to tell you more, but this should be enough.
2007-01-14 08:12:49 · answer #2 · answered by Hy 7 · 0⤊ 0⤋
1) 0.0367
2)0.5198
3)8.0598
4)-0.0150
tHE WORKING IS WITH A POCKET CALCLUATOR.
In the las casecos(.1)=0.9950 ln(0.9950)=-0.005
2007-01-14 08:50:01 · answer #3 · answered by santmann2002 7 · 0⤊ 0⤋
Take a calculator and punch in the values.
2007-01-14 08:19:36 · answer #4 · answered by ag_iitkgp 7 · 0⤊ 0⤋
(i)0.1^2 x e^(1.3)=0.037
(ii)4e^-2cos6=0.586
(iii)3/sin1 + 7/tan1=8.060
(iiii)3ln(cos)=3ln(cos0.1)
=-0.015
2007-01-14 08:09:52 · answer #5 · answered by A 150 Days Of Flood 4 · 0⤊ 0⤋