Back to Exercise: Know the Fundamental Theorem of Algebra

Exercises: Know the Fundamental Theorem of Algebra

For quadratic problems, show the discriminant. For root-counting, include multiplicity.

Grade 9·20 problems·~40 min·Common Core Math - HS Number and Quantity·standard·hsn-cn-c-9
Work through problems with immediate feedback
A

Warm-Up: Review What You Know

1.

The Fundamental Theorem of Algebra states that every non-constant polynomial of degree nn has exactly how many roots in the complex numbers?

2.

The polynomial p(x)=x2+1p(x) = x^2 + 1 has no real roots. Does the Fundamental Theorem of Algebra apply to p(x)p(x)?

3.

The polynomial p(x)=(x2)2(x+5)p(x) = (x - 2)^2(x + 5) has degree 33.

According to the FTA, how many roots does p(x)p(x) have in the complex numbers, counting multiplicity?

B

Fluency Practice

1.

Classify the discriminant case for x25x+6=0x^2 - 5x + 6 = 0 and identify the number of roots.

2.

Classify the discriminant case for x24x+4=0x^2 - 4x + 4 = 0 and identify the roots.

3.

Classify the discriminant case for x24x+5=0x^2 - 4x + 5 = 0 and identify the roots.

Discriminant $= $   ̲ ̲ ̲ ̲ ̲ ̲ ̲ ̲ ̲ ̲ ̲ ̲ ̲ ̲ ̲ ̲ ̲ ̲ ̲ ̲ ̲ ̲   (enter an integer). The roots are x=2±x = 2 \pm   ̲ ̲ ̲ ̲ ̲ ̲ ̲ ̲ ̲ ̲ ̲ ̲ ̲ ̲ ̲ ̲ ̲ ̲ ̲ ̲ ̲ ̲   ii.

discriminant value:
imaginary coefficient:
4.

The polynomial p(x)=(x1)(x+3)(x2+4)p(x) = (x - 1)(x + 3)(x^2 + 4) has degree 44.

How many total roots does p(x)p(x) have over the complex numbers, counting multiplicity?

5.

The polynomial p(x)=x4+1p(x) = x^4 + 1 has degree 44 and real coefficients. How many real roots does it have?

You're viewing 2 of 6 sections.

Create a free account to continue the full exercise set and save your progress.

Create free account
0 of 8 answered

Answer all problems to submit.