1.1 (a) p = 124.68; (b) q = 400; (c) r = 0.04.
1.2 (a) 756 = 22337; (b) .
1.3 (a) p = 1.246 × 103; (b) − 1.57 × 103; (c) 4.5 × 10− 3.
1.5 (a) 25/2311/12; (b) 3− 1/6512/5; (c) 77/32− 1/2.
1.6 (a) (b)
*1.7 (a) 10.31 = 1010.01012…; (b) 1101.012 = 13.25.
*1.8 (a) p × q = 321304; (b) (p − q) = 114.
1.9 (a) ; (b) ; (c) 35/6a− 5/3.
1.10 (a) identity; (b) equation.
1.11 (a) − 1 < x < 4; (b) − 4 < x < −2 or 2 < x < 4; (c) x > −2 or x < −4.
1.12 31.681.
1.13 − 9828a3b11.
1.17 (a) (b) (c) x = y6 + 2.
1.18
1.19 (a) (b) f− 1(x) = 27x3 − 4.
1.20 (a) y = −x + 3; (b) 3y = 2x − 7; (c) 2y + 5x = 13; (d) 5y + 2x = 22.
1.21
1.22 Area = 12.
1.23 (a) (x − 1)2 + (y − 3)2 = 4; (b) (x − 1)2 + (y − 3)2 = 13.
1.24 Centre , radius .
2.1 3x2 − 2x + 1 = 0.
2.3
2.4 and Angle at centre 2.42 rad = 139°.
2.5 (a) (x − 1)(x2 + 2x + 1) − 3.
2.6
2.7 1.526.
2.8 (a) ; (b) ; (c) .
2.9 (a) ; (b) ; (c) .
2.11 (a) θ = 0.666 and 2.475 radians; radians. (b) ; .
2.12 for all integer n and k ≠ 1, and for all integer n and k ≠ −1.
2.13 , .
2.15 A = 0.643 radians, C = 1.999 radians, c = 7.59 cm.
2.16 A = 0.809 radians, B = 1.391 radians, C = 0.942 radians.
2.18 (a) log (x2); (b) 0.
2.19 (a) x = 31.765; (b) x = 1.122.
2.20 (a) x = 32.66; (b) x = 3.401.
2.22 (a) or x = 0; (b) (c)
2.23 x = ±1.317.
2.24 t1t2 = −1.
2.25 tangent: y = x + 1; normal: y = −x + 3.
3.1 (a) 1; (b) 0; (c) 4.
3.2 (a) 10; (b) ; (c) 1.
3.5 (a) Removable discontinuity at x = 0; (b) Non-removable discontinuity at x = 3; removable discontinuity at x = −3.
3.6 (a) A = 1; (b) A = 1 and B = 0 (all n), or for n ≥ 2 (all B).
3.7 (a) 6x2 + 4; (b) (c) − 15sin 3x.
3.8 (a) x3ex + 3x2ex; (b) (c) (d) (e) (f)
3.9 (a) (b) (c) ; (d)
3.10 (a) xx(ln x + 1); (b) ; (c) ; (d) tan x.
3.11 (a) ; (b) .
3.12 .
3.13 ; .
3.14 x = −8 and , respectively.
3.15 , 7y = 6x − 21.
3.16 Three: f(1), f(2) and f(3).
3.17 (a) 2n − 1e2x + ( − 1)n + 12n − 1e− 2x; (b) , for all n ≥ 1.
3.19
3.20 (a) Minimum at x = 0, maxima at x = ±1.
3.21 Maxima at minima at
3.24 Approximate solutions: x = −0.8, 1.5 and 3.4.
3.27 Vertex x = 3a, y = 0.
4.1 Area = 16.41.
4.2 (b)
4.3 (a) (b) (c)
4.4 (a) (b) 2(3 + x − x2)1/2 + c;
4.5 (a) (b)
4.6 (a) (b)
4.7 (a) 2ln (x − 2) + 3ln (x + 1) + c; (b)
4.8 (a) (b)
4.9 (a) (b)
4.10 (a) tan xln (tan x) − tan x + c; (b)
4.11 (a) (b)
4.12 (a) (b) .
4.13 (a) (b) (c) –1.
4.15
4.16 (a) (b) (c)
4.17 (b) At x = 0 and all negative integers;
4.18 564 m.
4.19 (a) Convergent with value ; (b) convergent with value ; (c) divergent; (d) divergent.
4.21 (a) Converges for all α < −1; (b) Converges provided β > −1, α < −1.
4.22
4.23
4.24 L = 3.0896 (trapezium rule), L = 3.0847 (Simpson's rule).
4.25 π = 3.14294 for n = 2 and 3.14170 for n = 4. Four intervals are needed.
*4.26 A = 2π, , S = 3π.
*4.27
*4.28 (a) (b)
*4.29
*4.30
5.1 Sum = 148875.
5.2 where . No values of r.
5.3 , convergent as N → ∞.
5.4 .
5.5 (a) convergent; (b) divergent; (c) divergent; (d) convergent.
5.6 (a) |x| < 1; (b) ; (c) x < 0.
5.7 (a) ; (b) − π; (c) –1; (d)
5.8 (a) ; (b) 1.
5.9 , valid for all x.
5.10 3 terms give sin x = 0.56465, the calculator value is 0.56465.
5.11 (a) ; (b)
5.14
5.15 (a) ; (b)
5.16 0.838.
5.17 First minimum is at 4.50 rad = 258° to the nearest 1°.
5.20 ; valid for |x| < 1.
5.21 ; valid for all x.
5.22 (a) conditionally convergent; (b) absolutely convergent for α ≠ kπ, where k is an integer; (c) conditionally convergent for α = 0.
5.23 (a) conditionally convergent; (b) not convergent; (c) absolutely convergent; (d) absolutely convergent.
6.1 (a) − (1 + 2i); (b) − 5(1 + 2i); (c) 6(5 + 7i); (d) 4(3 − 4i);
6.3
6.5 (a) r = 1, ; (b) , ; (c) , .
6.7 (a) circle radius 4 centre (0, 3); (b) circle radius centre (0, 0); (c) converges for all z.
6.8 (a) and ; (b) and ; (c) and .
6.9 (a) − 0.101 − 0.346i; (b) 0.417 + 0.161i; (c) 1.272 − 0.786i and − 1.272 + 0.786i.
6.10 (a) 0.0313i, (b) 1.864 + 0.290i, − 1.183 + 1.468i and − 0.680 − 1.758i, (c) −i.
6.11 (a) 0.951 + 0.309i, i, − 0.951 + 0.309i, − 0.588 − 0.809i and 0.588 − 0.809i; (b) 0.080 + 0.440i; (c) 0.920 + 0.391i.
6.12 (a) 0.1080 + 0.4643i; (b) 3i/4; (c) − 0.805 + 1.007i.
6.13 (a)− 0.266 + 0.320i; (b) 4.248; (c)
6.14 (a) cos (12θ) + isin (12θ).
6.15 (a) cos 7θ − isin 7θ.
*6.16
*6.17 e2cos xsin (2sin x).
*6.18
7.3 , ; x + 2y + 3z = 14.
7.8 (a); (c) and (d)
7.9 (a) ; (b) f(x, y) = x2ln (xy) + k, k an arbitrary constant.
7.10 (a) y(4x + 3y3) − xy2(9x + 16y); (b) –2, (c) .
7.11 (a) satisfied k = 3; (b) not satisfied; (c) satisfied k = 0; (d) satisfied .
7.16
7.17
7.18 maximum , minimum –.
7.19 maximum (0, 0), saddle point ( − 1, 1).
*7.20 (0, −1), (2, 1), ( − 2, 1).
*7.21
*7.22
*7.23 (a) , I(x) = e− x − e− 1; (b)
*7.24 (a)
*7.25
8.1
8.3 (0, 4, 0).
8.4 (b) θ = 2.68 rad = 153.4°, direction cosines (0, 0, 1).
8.7 , area = .
8.9 .
8.10 (a) − 6i − 3j; (b) .
8.12 (a) τ = −9i + 6j + 5k; (b) τ = 3i − 2j; (c) τz = 5; (d) .
*8.15 (a) (b)
8.16 , .
8.17 , D is (0, 1, 0).
8.19 x − 2y − 3z = 7, .
8.20 x + 4y + 6z = 5.
8.21 θ = 1.52 rad = 87.2°; r = (2i − 3j) + s(i − 2j + k).
8.22 .
8.23 where c is a constant.
9.1 a × b = 7i + 10j − 9k, b · a × c = 52.
9.2 (a) 16 + 5i; (b) –1.
9.3 –105.
9.4 (a) x = 0, 1 or − 2; (b) Δ2 = (α + β + γ)(α − β)(β − γ)(γ − α).
9.5 Δn = (n + 1)( − 1)n.
9.6 (a) no non-trivial solution; (b) x: y: z = −3: 1: 1.
9.7 α = 3 and 14. For the latter, .
9.13 (a) (A + B)3 = (A3 + A2B + ABA + AB2 + BA2 + BAB + B2A + B3); (b) AB = BA.
9.15 (b)
9.19 and .
9.20
9.21
9.22 ma = 960 gm, mb = 120 gm.
9.23 (a) α ≠ 3, independent of the value of β; (b) ; (c) (i) β = 6, a solution exists, but is not unique; (ii) β = 2, no solutions exist.
10.1 . Normalised eigenvectors are:
Eigenvectors not orthogonal.
10.7 Eigenvalues: λ = 0, 1. Linearly independent eigenvectors: , (λ = 0) and , (λ = 1).
The matrix is defective.
10.9 (a) Eigenvalues: . Corresponding normalised eigenvectors:
Eigenvectors not orthogonal.
(b) Eigenvalues: . Corresponding normalised eigenvectors:
10.10
*10.12
*10.15
*10.16 Principal axes along: 2x + 2y + z = 0, 2x − y − 2z = 0, x − 2y + 2z = 0, shortest distance is 2.
*10.17 (a) oblate spheroid; (b) one-sheet hyperboloid.
*10.19 to the x-axis. The two branches are closest at .
11.1 (a) 11; (b) .
11.2 (a) ; (b) .
11.3 2π.
11.4 (a) − 4π; (b) − 16.
11.5 (a) ; (b) 3.
11.6 1 − ln 2.
11.7 11.
11.9 (a) 2ln 2 − 1; (b) .
11.10 27.
11.11 0.
11.12 .
11.13 .
11.14 (a) 11; (b)
11.15 .
11.16 .
11.17 .
11.20 .
11.21 .
11.22 .
11.23
12.1 in direction − 2i + j; direction of most rapid decrease at (–3, 2) is 3i + 2j; .
12.2 (a) 2i − 2j − k; (b) (c) (1, 1, 1) + (2, −2, 1)t.
12.3 (a) y i − (3z3 − 4xz)j; (b) x2z(3xz3 + 2y2)i + 3x2yz2(2x − 3z2)j − 3xz2(y2 + x2z)k; (c) ( − 4x + 9z2)i + (4z − 1)k; (d) − 2yz2i + z2(3z2 − 2x)j + 4yz(3z2 − x)k; (e) 0.
12.6 (a) r2sin 2θsin φ;
(b) rsin θsin φ(sin θcos φ − cos θ) er + rsin θsin φ (cos θcos φ + sin θ) eθ + rsin θcos 2φ eφ;
(c)
(d) .
12.7 − 2πa4.
12.8 2π.
12.9 .
12.10 (a) ; (b) a3.
12.11 − 1.
12.12 − y2cosh 2(xz) + c, c constant
12.13 a = 4; b = 2; c = −1, d constant.
12.14 114.
12.15 2.
12.16 .
12.17 (a) ; (b)
12.18 Ma2/4 + Md2/3.
12.19 1.
*12.23 (b) (c) .
*12.24 (b) ρ0(r)e− σt/ϵ.
12.27 (a) 0; (b) 0; (c) no.
13.1
13.2
13.3
13.5 (a); (b); (d) do not satisfy Dirichlet conditions; (c) does satisfy Dirichlet conditions. (c)
13.6
13.7
13.8
13.9 , (b) is a valid series, but is an invalid series.
13.11
13.13
13.14
13.15
13.17
13.18
13.19 (a) (b) (c) .
13.20 (b) .
*13.22 .
*13.23 (a) I1 = I2 = π; (b) .
14.1 (a) ; (b) .
14.2 (a) (x − y − 2) − ln (x + y + 1) = 0; (b) .
14.4 .
14.5
14.6 (a) not exact; (b) exact, y2ln x = c.
14.7 (a) 2x3 − 6x2y + 3y2 − 6y + c = 0; (b) .
14.8 (a) x2(sin x − xcos x + c); (b) 2ysin x − cos 2x + c = 0.
14.9 (a) , (b) 2(x + 1)5/2 + (x + 1)2.
14.10 .
14.11 (a) ; (b) e− 3x(3cos 2x + 8sin 2x).
14.14 (a) ; (b) .
14.15 (a) (Ax + B)e− 2x + 2x2e− 2x; (b)
14.16 (a) ; (b) .
14.17
14.18 .
14.19 .
*14.20 .
*14.21
*14.23
*14.24 Ax + Bx− 3 + xln x + 1.
*14.25
15.2 .
15.3 .
15.4 .
15.5 .
15.6 .
15.8 .
15.9 λn = 1 + n2π2, yn(x) = Ansin (nπx).
15.10 λ2n = n2π2, .
*15.11
15.12
*15.14
*15.17
*15.18 k = 3.8317, 7.0156, 10.1735, 13.3237.
15.20 J2(2) = 0.35283 to 5 decimal places, 1 extra term for 7 decimal places.
*15.22 , .
16.1
16.2 n > 0.
16.3 .
16.5 .
16.6 where .
16.7 an, bn arbitrary constants.
16.9 .
16.11
16.13
16.14 .
16.16 4.878.
*16.17 (a) ; (b)
*16.18 (a) (b) f(x + 3y) + xg(x + 3y); (c) (d) .
*16.19