Find and correct the errors in the statement: (y − 3)^2 = y^2 − 9
Answers
Given : (y − 3)² = y² − 9
Concept :
Common errors we done by solving algebraical expression and equation:
Error 1
Coefficient 1 of a term is usually not written. So we often ignore that. But while adding like terms, we should include it in the sum.
Error 2
When we multiply the expression enclosed in a bracket by a constant (or a variable) outside, we usually applied the multiplication to the first term only. This is the wrong calculation. Each term of the expression has to be multiplied by the constant (or the variable).
Error 3
when we square a monomial, we usually ignored the numerical coefficient. This is the wrong method. The numerical coefficient and each factor has to be squared.
Error 4
when we square a binomial, we usually do not apply the proper identity. This is the wrong approach. The right identity should be used.
Error 5
While dividing a polynomial by a monomial, We usually don’t divide each term of the polynomial in the numerator by the monomial in the denominator.
Solution:
We have : (y − 3)² = y² − 9
LHS = (y - 3)² = y² - 6y + 9
[(a - b)² = a² + b² - 2ab]
RHS = y² - 9
LHS ≠ RHS
Correct statement :
(y - 3)² = y² - 6y + 9
Hope this answer will help you….
Some more questions related to this chapter :
Find and correct the errors in the statement: 5y + 2y + y − 7y = 0
https://brainly.in/question/17208933
Find and correct the errors in the statement: (3x + 2)^2 = 3x^2 + 6x + 4
https://brainly.in/question/17208936
Step-by-step explanation:
1)x(3x+2)=3x
2
+2
Here, the product of x with 3x+2 is not correct.
The correct product will be :
x(3x+2)=3x
2
+2x
2)5y+2y+y−7y=0
Here, the right hand side will not be zero.
The correct mathematical statement will be :
5y+2y+y−7y=y