Class 8 Algebraic Identities
65 videos • 3,261 views • by Mathematics Learning This playlist contains videos for learning algebraic identities.Class 8 Mathematics Ch 7 Algebraic Identities Algebraic Expressions|Variable|Constant|Operations|Terms|Coefficient|Monomial|Binomial|Trinomial|Identity|Algebraic identity (a+b)^2 https://youtu.be/YDbzJYOPawo Algebraic Identities https://youtu.be/rL3YQ9KYH6k Identity 1: (a+b)^2 WS1 Q1 https://youtu.be/EYsEUbTSSNA Identity 1: (a+b)^2 WS1 Q2 https://youtu.be/o_DUshFTN0Y Identity 2: (a-b)^2 WS2 Q1 Find the following (i) (x-7)²(ii) (5a-4b)²(iii) ((7x/4)-(2y/3))² https://youtu.be/1lw5jx4eFnY Identity 2: (a-b)^2 WS2 Q2 Evaluate the following using identity (i) (48)²(ii) (9.9)²(iii) (299)² https://youtu.be/wzLomO-GTUg WS3 Discussion of all problems based on identity 3: a² -b² = (a-b)(a+b) https://youtu.be/DP7J2LGBTqk Type 1 - Find the product (i) (2x+7y)(2x-7y) (ii)(5ab-8c)(5ab+8ac) (iii) (4p² + q²)(4p² - q²) (iv) (x/3 -y/2)(x/3+y/2) Type 2- Evaluate (i)(81² - 19²) (ii)(290² - 210²) (iii) (58² - 12²) (iv)(176² - 24²) (v) (367² - 33²) (vi)(545² - 445²) Type 3- Simplify (i) 107 x 93 (ii) 211 x 189 (iii) 195x205 (iv) 308x292 (v) 12.4x11.6 (vi) 30.9x29.1 WS3 Q1 Find the product (i) (2x+7y)(2x-7y) (ii)(5ab-8c)(5ab+8ac) (iii) (4p² + q²)(4p² - q²) (iv) (x/3 -y/2)(x/3+y/2) https://youtu.be/oyPObsO9f0g WS3 Q2 Evaluate (i) (81)²-(19)² (ii) (290)²-(210)² (iii) (58)²-(12)² https://youtu.be/qQsSsTWQY9o WS4 Expand the following https://youtu.be/KcBrHDx-378 (i) (x-2y+3z)² (ii) (-5x+2y+z)² (iii) (4x+y-3z)² (iv) (3a-5b-7c)² (v) (-2a-b+3c)² WS4 Q1 (i) (x-2y+3z)² https://youtu.be/ghJ0zpINnls WS4 Q2 (ii) (-5x+2y+z)² https://youtu.be/mLTtPN8CWCY WS5 Find the product by using suitable identity https://youtu.be/MC6mmK22Vrs (i) (x+5)(x+4) (ii) (a+3)(a+6) (iii) (x-9)(x+7) Geometrical representation of algebraic identity (a+b)² = (a² + 2ab + b²)https://youtu.be/MR8muglizrc Geometrical representation and verification of algebraic identity (a-b)² = (a² - 2ab + b²)https://youtu.be/jwV9YbasR6g Geometrical representation and verification of algebraic identity a² -b² = (a+b)(a-b) https://youtu.be/Xv3mbMCTC4c Geometrical representation of algebraic identity (a+b+c)² https://youtu.be/bmFvxThC6RU Brain Teasers Q1 B (a) Find the product using suitable identity.(a+3) (a-3)(a² +9) https://youtu.be/x8lzbHA9BMA Q1 B (b) If x^2 + 1/x^2 = 6 , find x^4 + 1/x^4 https://youtu.be/Tw23nWBPa98 Q1 B (c) Find the value of k if xy²k = 4(4x+3y)²-(4x-3y)² https://youtu.be/ki34r82aarM Q2 (vi) Find the product using suitable identity [x+1/x][x-1/x][x²+1/x²][x⁴+1/x⁴] https://youtu.be/4DqYaRWIM8w Q6 Evaluate x (i)if 36x =78²-42² (ii)6.2x =8.1x8.1-1.9x1.9 https://youtu.be/BKtlA-vNePc Q8 if x+1/x = 8 then find x²+1/x² https://youtu.be/sZJf_Cy0ULY Q13 if 3x - 4y = 10 and xy = -1 then find the value of 9x²+16y² https://youtu.be/58UdnT7Ywzw Q14 If 5x-2y= 7 and xy=2 , find the value of (5x+2y)² https://youtu.be/5W91sZTLRIE Q15 https://youtu.be/IFJeum1NAsM Practice Questions if x+1/x = 5 then find x²+1/x² https://youtu.be/xAy7xXtGdGM Factorise (4a)² -(b-c)² https://youtu.be/s-o2DQLYy9k Show that. (i) (3x + 7)² – 84x = (3x – 7)² (ii) (9p – 5q)²+ 180pq = (9p + 5q)² (iii) (4pq + 3q)²– (4pq – 3q)² = 48pq² (iv) (a – b) (a + b) + (b – c) (b + c)+ (c – a) (c + a) = 0 https://youtu.be/eE2SuMTQP9M Hands on activities Verification of (a+b+c)^2 https://youtu.be/REzurdsaJZU Verification of (a^2 - b^2) https://youtu.be/rTkI2kvhQHI