if a and b are two zero of polynomial 5xsq -7x+3 find value of a sq +bsq
Answers
Step-by-step explanation:
see the attachment.....
Answer:
a² + b² = 19/25
Note:
★ The possible values of the variable for which the polynomial becomes zero are called its zeros .
★ A quadratic polynomial can have atmost two zeros.
★ If a and b are the zeros of the quadratic polynomial Ax² + Bx + C , then ;
• Sum of zeros , (a + b) = -B/A
• Product of zeros , (ab) = C/A
Solution:
Here,
The given quadratic polynomial is ;
5x² - 7x + 3 .
On comparing with the general form of the quadratic polynomial Ax² + Bx + C ,
We have ;
A = 5
B = -7
C = 3
Also,
It is given that , a and b are the zeros of the given quadratic polynomial .
Thus,
=> Sum of zeros = -B/A
=> a + b = -(-7)/5 = 7/5
Also,
=> Product of zeros = C/A
=> ab = 3/5
Now ,
We know that ;
=> (a + b)² = a² + 2ab + b²
=> a² + b² = (a + b)² - 2ab
=> a² + b² = (7/5)² - 2•(3/5)
=> a² + b² = 49/25 - 6/5
=> a² + b² = (49 - 30)/25
=> a² + b² = 19/25