test: added some interesting and missing tests.

Author: hemalvarambhia

src/Math-Tests-Polynomials/PMPolynomialTest.class.st

@@ -242,6 +242,25 @@ PMPolynomialTest >> testPolynomialRoots [
 	self assert: (roots at: 3) - 5 closeTo: 0
 ]
 
+{ #category : #'iterative algorithms' }
+PMPolynomialTest >> testPolynomialRootsForConstant [
+	| polynomial |
+	"Here, compute the roots of the quadratic (2x + 1)"
+	polynomial := PMPolynomial coefficients: #(1).
+	self should: [ polynomial roots ] raise: Error description: 'Function''s derivative seems to be zero everywhere'.
+	
+]
+
+{ #category : #'iterative algorithms' }
+PMPolynomialTest >> testPolynomialRootsForLinear [
+	| polynomial roots |
+	"Here, compute the roots of the quadratic (2x + 1)"
+	polynomial := PMPolynomial coefficients: #(1 2).
+	roots := polynomial roots .
+	self assert: roots size equals: 1.
+	self assert: (roots at: 1) closeTo: -0.5 .
+]
+
 { #category : #'iterative algorithms' }
 PMPolynomialTest >> testPolynomialRootsForQuadratic [
 	| polynomial roots |