• Basic forms
• 試みる — attempt; endeavor / base form
• 試みます — attempts / masu form
• 試みた — attempted / ta form
• 試みて — attempting … / te form
• 試みない — do not attempt / negative
• 試みれば — if (one) attempts / conditional
• Common expressions
• 改革を試みる — attempt reform
• 新しい方法を試みる — attempt a new approach
• 改善を試みる — seek improvement

試みる（こころみる） is an ichidan transitive verb. It is relatively formal and is used for deliberate or planned attempts, often in written or academic contexts.

• Basic forms
• 試す — try; test / base form
• 試します — tries; tests / masu form
• 試した — tried; tested / ta form
• 試して — trying … / te form
• 試さない — do not try / negative
• 試せば — if (one) tries / conditional
• Common expressions
• 方法を試す — try a method
• 能力を試す — test ability
• 新製品を試す — try a new product
• More
• 試してみる — give it a try

試す（ためす） is a godan transitive verb. It is common in everyday speech and is used for practical testing, experimentation, or casual trying.