BSE Odisha 8th Class Maths Solutions Algebra Chapter 5 ସୂଚକ ତତ୍ତ୍ଵ Ex 5(b)

Odisha State Board BSE Odisha 8th Class Maths Solutions Algebra Chapter 5 ସୂଚକ ତତ୍ତ୍ଵ Ex 5(b) Textbook Exercise Questions and Answers.

BSE Odisha Class 8 Maths Solutions Algebra Chapter 5 ସୂଚକ ତତ୍ତ୍ଵ Ex 5(b)

Question 1.
ନିମ୍ନଲିଖ ରାଶିଗୁଡ଼ିକୁ ଏକ ଆଧାର ବିଶିଷ୍ଟ ଘାତ ରାଶି ରୂପେ ପ୍ରକାଶ କର ।
(i) 3⁶ × 3⁴
(ii) \(\left(\frac{1}{2}\right)^6 \times\left(\frac{1}{2}\right)^5\)
(ii) \(\left(\frac{2}{3}\right)^7 \times\left(\frac{2}{3}\right)^3\)
(iv) (4)⁶ × (-4)^-3
(v) \(\left(\frac{3}{2}\right)^5 \times\left(\frac{2}{3}\right)^4\)
(vi) (-4)⁶ × (4)³
(vii) (9)³ × (27)⁴
(viii) (8)³ × (-4)⁴
(ix) (7)⁸ × (-7)⁵
(x) (8)⁵ ÷ (4)⁴
(xi) {(5)³}⁴
(xii) {(-2)³}⁴
(xiii) \(\frac{7^4}{3^4}\)
(xiv) (3)⁹ + (4)⁹
(xv) \(\left(\frac{a}{b}\right)^7 \div\left(\frac{b}{a}\right)^3\)
(xvi) \(\left(\frac{a}{b}\right)^7 \div\left(\frac{-b}{a}\right)^3\)
ସମାଧାନ :
(i) 3⁶ × 3⁴ = (3 × 3 × 3 × 3 × 3 × 3) × (3 × 3 × 3 × 3)
= 3 × 3 × 3 × 3 × 3 × 3 × 3 × 3 × 3 × 3 = 3¹⁰
ବିକଳ୍ପ ପ୍ରଣାଳୀ : 3⁶ × 3⁴ = 3⁶⁺⁴ = 3¹⁰

(ii) \(\left(\frac{1}{2}\right)^6 \times\left(\frac{1}{2}\right)^5=\left(\frac{1}{2}\right)^{6+5}=\left(\frac{1}{2}\right)^{11}\)

(iii) \(\left(\frac{2}{3}\right)^7 \times\left(\frac{2}{3}\right)^3=\left(\frac{2}{3}\right)^{7+3}=\left(\frac{2}{3}\right)^{10}\)

(iv) (4)⁶ × (-4)^-3 = (4)⁶ × (-1 × 4)³
= (4)⁶ × (-1)³ × (4)³ = (-1)³ × (4)⁶ × (4)³
= (-1) × 4⁶⁺³ = (-1)⁹ × 4⁹ = (-1 × 4)⁹ = (-4)⁹

(v)

(vi) (-4)⁶ × (4)³ = (-1 × 4)⁶ × (4)³
= (-1)³ × (4)⁶ × (4)³ = 1 × 4⁶⁺³ = (4)⁹

(vii) (9)³ × (27)⁴ = (3²)³ × (3³)⁴
= 3^2×3 × 3^3×4
= 3⁶ × 3¹² = 3⁶⁺¹² = 3¹⁸

(viii) (8)³ × (-4)⁴ = (8)³ × (-1 × 4)⁴ = (8)³ × (-1)⁴ × (4)⁴
= (-1)⁴ × 8³ × (4)⁴ = 1 × (2³)³ × (2²)⁴ = 2⁹ × 2⁸ = 2⁹⁺⁸ = 2¹⁷

(ix) (7)⁸ × (-7)⁵ = 7⁸ × (-1 × 7)⁵
= 7⁸ × (-1)⁵ × 7⁵ = (-1)⁵ × 7⁸ × 7⁵ = -1 × 7⁸⁺⁵
= -1 × 7¹³ = (-1)¹³ × 7¹³ = (-1 × 7)¹³ 4= (-7)¹³

(x) (8)⁵ ÷ (4)⁴ = ((2)³)⁵ ÷ ((2)²)⁴ = (2)¹⁵ ÷ (2)⁸ = 2^15-8 = 2⁷

(xi) {(5)³}⁴ = 5^3×4 = 5¹²

(xii) {(-2)³}⁴ = (-2)^3×4 = (-2)¹²

(xiii) \(\frac{7^4}{3^4}\) = \((\frac{7}{3})^4\)

(xiv) (3)⁹ ÷ (4)⁹ = \((\frac{3}{4})^9\)

(xv)

(xvi) \(\left(\frac{a}{b}\right)^7 \div\left(\frac{-b}{a}\right)^3\)

Question 2.
ମାନ ନିର୍ଣ୍ଣୟ କର ।
(i) 3⁴ × 3³ ÷ 3⁵
(ii) (3¹¹ × 4⁵) ÷ (4⁴ × 3⁶)
(iii) (4³ × 4² × 4) ÷ (2⁴ × 2³ × 2²)
(iv) 2¹¹ ÷ 8³ × 4²
(v) \(\left(\frac{3}{2}\right)^6 \div\left(\frac{2}{3}\right)^2\)
ସମାଧାନ :
(i) 3⁴ × 3³ ÷ 3⁵
= \(3^4 \times\left(\frac{3^3}{3^5}\right)=3^4 \times \frac{1}{3^{5-3}}=3^4 \times \frac{1}{3^2}=\frac{3^4}{3^2}=3^{4-2}=3^2=9\)

(ii) (3¹¹ × 4⁵) ÷ (4⁴ × 3⁶)
= \(\frac{3^{11} \times 4^5}{4^4 \times 3^6}=\frac{3^{11}}{3^6} \times \frac{4^5}{4^4}=3^{11-6} \times 4^{5-4}\) = 3⁵ × 4 = 243 × 4=972

(iii) (4³ × 4² × 4) ÷ (2⁴ × 2³ × 2²)
= 4³⁺²⁺¹ ÷ 2⁴⁺³⁺² = 4⁶ ÷ 2⁹
= (2²)⁶ ÷ 2⁹ = 2¹² ÷ 2⁹ = 2^{12 – 9} = 2³ = 8

(iv) 2¹¹ ÷ 8³ × 4² = 2¹¹ ÷ (2³)³ × (2²)²
= 2¹¹ ÷ 2^3×3 × 2^2×2 = 2¹¹ ÷ 2⁹ × 2⁴ = 2^11-9 × 2⁴ = 2² × 2⁴ = 2²⁺⁴ = 2⁶ = 62

(v)

Question 2.
ସରଲ କର ।
(i) (2² × 2)³
(ii) (ab)⁵ × a³ × b²
(iii) \(\left(\frac{a}{b}\right)^7 \times a^6 \times b^5 \times\left(\frac{b}{a}\right)^6\)
(iv) 3⁹ × 3⁵+ 9⁷
(v) \(\left(\frac{2}{3}\right)^5 \div\left(\frac{2}{3}\right)^8 \times\left(\frac{2}{3}\right)^3\)
ସମାଧାନ :
(i) (2² × 2)³ = (2²⁺¹)³ = (2³)³ = 2^3×3 = 2⁹ = 512

(ii) (ab)⁵ × a³ × b² = a⁵ × b⁵ × a³ × b²
= (a⁵ × a³) × (b⁵ × b²) = a⁵⁺³ × b⁵⁺² =a⁸b⁷

(iii) \(\left(\frac{a}{b}\right)^7 \times a^6 \times b^5 \times\left(\frac{b}{a}\right)^6\) = \(\left(\frac{a^7}{b^7}\right) \times a^6 \times b^5 \times\left(\frac{b^6}{a^7}\right)\)

(iv) 3⁹ × 3⁵ ÷ 9⁷ = 3⁹ × 3⁵ ÷ (3²)⁷ = 3⁹ × 3⁵ ÷ 3^2×7
= 3⁹ × 3⁵ ÷ 3¹⁴ = 3⁹ × \(\frac{3^5}{3^14}\) = 3⁹ × \(\frac{1}{3^14-5}\) = \(\frac{3^9}{3^9}\) = 1

(v)

Question 4.
ମୌଳିକ ଆଧାର ବିଶିଷ୍ଟ ଘାତରାଶିରେ ପ୍ରକାଶ କର ।
(i) (64)³
(ii) (9)⁷
(iii) (125)^m-1
(iv) (-8)¹¹
ସମାଧାନ :
(1) 64³ = (2⁶)3 = 2^6×3 = 2¹⁸ [∵ 64 ର ଏକ ମୌଳିକ ଗୁଣନୀୟକ 2]
(ii) (9)⁷ = (3²)⁷ = 3^2×7 = 3¹⁴ [∵ 9 ର ଏକ ମୌଳିକ ଗୁଣନୀୟକ 3]
(iii) (125)^m-1 = (5³)^m-1 = 5³(^m-1) = 5^3m-3 [125 ର ଏକ ମୌଳିକ ଗୁଣନୀୟକ 5]
(iv) (-8)¹¹ = {(-2)¹¹}¹¹ = (-2)¹¹ = (-2)¹¹ [(-8) ର ମୌଳିକ ଗୁଣନୀୟକ -2]

Question 5.
ନିମ୍ନଲିଖ୍ତ ଉକ୍ତି ମଧ୍ୟରୁ ଠିକ୍ ଉକ୍ତି ପାଇଁ (T) ଓ ଭୁଲ୍ ଉକ୍ତି ପାଇଁ (F) ଲେଖ ।
(i) 2³ × 3⁵ = 6⁸
(ii) 3⁵ × 5⁵ = 15⁵
(iii) (4³)⁴ = (4)⁷
(iv) (5²)³ = 5⁶
(v) (3)³ × (3)² = 3⁶
(vi) (a³ . b⁵) = (ab)¹⁵
(vii) (2³ × 3³) = 6³
(viii) \(\left(\frac{3}{4}\right)^6 \div\left(\frac{4}{3}\right)^2=\left(\frac{3}{4}\right)^4\)
(ix) (3)⁴ × (3)⁵ × (-3)² = (-3)¹¹
(x) -3⁴ × 3³ = -3^{7
ସମାଧାନ :}
(i) F
(ii) T
(iii) F
(iv) T
(v) T
(vi) F
(vii) T
(viii) F
(ix) F
(x) F

Question 6.
କେଉଁ କ୍ଷେତ୍ରରେ n ଏକ ଗଣନ ସଂଖ୍ୟା ହେବ ?
(i) 2ⁿ = 32
(n) 5ⁿ = loo
(iii) 4ⁿ = 512
(iv) 4ⁿ = 1024
(v) 3ⁿ = 729
(vi) 5ⁿ = 1250
(vii) 7ⁿ = 343
(viii) (\(\frac{1}{2}\))ⁿ = \(\frac{1}{64}\)
(ix) (\(\frac{2}{3}\))ⁿ = \(\frac{32}{15}\)
(x) (-2)ⁿ = -512
ସମାଧାନ :
ପ୍ରତ୍ୟେକ କ୍ଷେତ୍ରରେ ଉଭୟ ପାର୍ଶ୍ଵର ଆଧାର ସମାନ କରି ଘାତଦ୍ଵୟ ମଧ୍ଯରେ ସମ୍ବନ୍ଧ ନିରୂପଣ କର ଏବଂ ଉଦ୍ଧୃତ ସମ୍ବନ୍ଧରୁ ‘n’ କେଉଁ ପ୍ରକାରର ସଂଖ୍ୟା ସ୍ଥିର କର ।
(i) 2ⁿ = 32 ⇒ 2ⁿ=2ⁿ ⇒ n = 5, ଏଠାରେ n ଏକ ଗଣନ ସଂଖ୍ୟା ।
(ii) 5ⁿ = 100 ⇒ 5ⁿ = 5² × 4, ଏଠାରେ n ଏକ ଗଣନ ସଂଖ୍ୟା ନୁହେଁ ।
(iii) 4ⁿ = 512 ⇒ (2²)ⁿ = 2⁹ ⇒ 2n = 9 ⇒ n =
(iv) 4ⁿ = 1024 ⇒ (2²)ⁿ = 2¹⁰ ⇒ 2²ⁿ = 2¹⁰ ⇒ 2n = 10 ⇒ n = 5, ଏଠାରେ n ଏକ ଗଣନ ସଂଖ୍ୟା ।
(v) 3ⁿ = 729 ⇒ 3ⁿ = 3⁶ ⇒ n = 6, ଏଠାରେ n ଏକ ଗଣନ ସଂଖ୍ୟା ।
(vi) 5ⁿ = 1250 ⇒ 5ⁿ = 5⁴ × 2, ଏଠାରେ n ଏକ ଗଣନ ସଂଖ୍ୟା ନୁହେଁ ।
(vii) 7ⁿ = 343 ⇒ 7ⁿ = 7³ ⇒ n = 3, ଏଠାରେ n ଏକ ଗଣନ ସଂଖ୍ୟା ।
(viii) \(\left(\frac{1}{2}\right)^{\mathrm{n}}=\frac{1}{64} \Rightarrow\left(\frac{1}{2}\right)^{\mathrm{n}}=\left(\frac{1}{2}\right)^6\) ⇒ n = 6, ଏଠାରେ n ଏକ ଗଣନ ସଂଖ୍ୟା ।
(ix) (\(\frac{2}{3}\))ⁿ = \(\frac{32}{15}\) ⇒ (\(\frac{2}{3}\))ⁿ = \(\frac{2^5}{3×5}\) ଏଠାରେ n ଏକ ଗଣନ ସଂଖ୍ୟା ନୁହେଁ ।
(x) (-2)ⁿ = -512 ⇒ (-2)ⁿ = (-2)⁹ ⇒ n = 9, ଏଠାରେ n ଏକ ଗଣନ ସଂଖ୍ୟା ।