if 0and 1 are the zeros of the polynomial f(x) 2x cube +3x square +ab+b find the value of a and b plzz tell me fast
Answers
Correct Question:
- If 0 and 1 are the zeroes of the polynomial p(x) 2x³ - 3x² + ax + b then find the value of a and b.
Given:
- 0 and 1 are the zeroes of the polynomial 2x³ - 3x² + ax + b.
To Find:
- Value of a and b
Solution:
Let p(x) = 2x³ - 3x² + ax + b
★Case I :
0 is zero of the p(x) = 2x³ - 3x² + ax + b
Now,
→ p(0) = 2(0)³ - 3(0)² + a(0) + b
→ p(0) = 0 - 0 + 0 + b = 0
→ p(0) = b = 0 --(1)
★Case II :
1 is zero of the p(x) = 2x³ - 3x² + ax + b
Now,
→ p(1) = 2(1)³ - 3(1)² + a(1) + b
→ p(1) = 2 - 3 + a + b = 0
→ p(1) = -1 + a + 0 = 0 [From eq 1]
→ p(1) = a = 1
Hence,
- a = 1
- b = 0
Correct Question
- If 0 and 1 are the zeroes of the polynomial f(x) = 2x³ - 3x² + ax + b, then find the value of a and b.
⠀
Given
- Polynomial f(x) = 2x³ - 3x² + ax + b.
- Two zeroes of the polynomial are 0 and 1.
⠀
To find
- Value of a and b.
⠀
Solution
- Let us consider two cases.
⠀
⠀
⠀⠀⠀⠀⠀⠀⠀⠀⠀When f(0) = 0
⠀
→ f(0) = 2(0)³ - 3(0)² + a(0) + b
→ f(0) = (2 × 0) - (3 × 0) + 0 + b
→ f(0) = 0 - 0 + b
→ f(0) = b
⠀
★ Putting f(0) = 0, we get
⠀⠀.....[1]
⠀
⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀
⠀
⠀
⠀⠀⠀⠀⠀⠀⠀⠀⠀When f(1) = 0
⠀
→ f(1) = 2(1)³ - 3(1)² + a(1) + b
→ f(1) = (2 × 1) - (3 × 1) + a + b
→ f(1) = 2 - 3 + a + b
→ f(1) = -1 + a + b
⠀
★ Putting p(1) = 0, we get
→ -1 + a + b = 0
→ a + b = 1
⠀⠀
★ From eq[1]
→ a + 0 = 1
⠀
Hence,
- Value of a = 1
- Value of b = 0
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