Grade 8 Identities Worksheet (For CBSE, ICSE, IAS, NET, NRA 2022)

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(1) Use the Identities to Expand the Following Algebraic Expressions

(a)

(b)

(c)

(2) Use the Identities to Expand the Following Algebraic Expressions

(a)

(b)

(3) Use the Identities to Rewrite Each Algebraic Expression as a Square of a Binomial

(a)

(4) Use the Identities to Rewrite Each Algebraic Expression as a Square of a Binomial

(a)

(5) Use the Identities to Answer These Questions

(a)

(6) Use the Identities to Answer These Questions

(a)

(7) Use the Identities to Answer These Questions

(a) Find , when

(8) Use the Correct Identity to Solve the Following Problems

(a)

(b)

(9) Use the Correct Identity to Solve the Following Problems

(a)

(b)

(10) Use the Identities to Expand the Following Algebraic Expressions

(a)

(b)

(11) Use the Identities to Answer These Questions

(a) If , find

(b) If , find the value of

(12) Use the Identities to Answer These Questions

(a) If find the value of

(13) Use the Identities to Answer These Questions

(a) If , find the value of

Answers and Explanations

Answer 1 (A)

  • Here given algebraic expression is,

  • Hence
  • Now,

Answer 1 (B)

  • Here given algebraic expression is,

  • Hence
  • Now,

Answer 1 (C)

  • Here given algebraic expression is,

  • Hence
  • Now,

Answer 2 (A)

  • Here given algebraic expression is,

  • Hence
  • Now,

Answer 2 (B)

  • Here given algebraic expression is,

  • Hence
  • Now,

Answer 3 (A)

  • Given algebraic expression is;

  • Now compare this algebraic expression with So we have,

  • Hence from above ,

  • Hence,

  • So, algebraic expressions as a square of a binomial

Answer 4 (A)

  • Given algebraic expression is;

  • Now compare this algebraic expression with So we have,

  • Hence from above ,

  • Hence,

  • So, algebraic expressions as a square of a binomial

Answer 5 (A)

  • To answer this with the use identities we first consider
  • Answer of above will multiply with remaining expression for further solution
  • Hence , first part

  • Now compare our algebraic expression with identities
  • Hence,

  • From above,
  • Hence,

  • Now, second part

  • Now compare our algebraic expression with identities
  • Hence,
  • From above
  • Hence,

  • Hence,

Answer 6 (A)

  • Now we know the identities that,

  • Hence

  • Put the value of in above equation

Answer 7 (A)

  • Given values are,

  • Now we know the identities that,

  • Hence,

  • Put the value in above equation,

Answer 8 (A)

  • Given problem,
  • We know the identities that,

  • Compare our equation with identities expression than,

  • Hence
  • Put the value of a and b in expression,

  • Hence

Answer 8 (B)

  • Given problem,
  • We know the identities that,

  • Compare our equation with identities expression than,

  • Hence
  • Put the value of a and b in expression,

  • Hence,

Answer 9 (A)

  • We know the identities that

  • Compare our equation with identities expression than,

  • Put the values of a and b in expression than,

Answer 9 (B)

  • We know the identities that

  • Compare our equation with identities expression than,

  • Put the values of a and b in expression than,

Answer 10 (A)

  • Given algebraic expression,

  • We know the identities that ,

  • Now compare our polynomial with identities than,

  • Now,

Answer 10 (B)

  • Given algebraic expression,

  • We know the identities that ,

  • Now compare our polynomial with identities than,

  • Now,

Answer 11 (A)

  • We know the identities expression that,

  • Hence,

  • Now put the value of in above equation,

Answer 11 (B)

  • We know the identities expression that,

  • Hence,

  • Now put the value of in above equation,

  • We know the identities expression that,

  • Hence

  • Now put the value of and In above equation,

Answer 12 (A)

  • We know the identities that,

  • Hence

  • Now put the value of in above equation than,

  • Now we know the identities expression that,

  • We put

  • Put the value of and

Answer 13 (A)

  • We know the identities that,

  • Now put the value of

  • Now put the value of in above equation than,

  • Now we know the identities expression that,

  • we put

  • Put the value of

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